Initial commit
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# Breadboard Game Boy
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A Game Boy version of the 8-bit computer built by Ben Eater in his [series of videos](https://eater.net/8bit).
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[Here is a blog post about it.](https://austinmorlan.com/posts/8bit_breadboard_gameboy/)
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![Emulator Demo](https://austinmorlan.com/posts/8bit_breadboard_gameboy/media/count_emu.gif)
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![Hardware Demo](https://austinmorlan.com/posts/8bit_breadboard_gameboy/media/count_hw.gif)
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#!/usr/bin/env bash
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CODE_DIR=code
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BUILD_DIR=build
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TEMP_DIR=$BUILD_DIR/temp
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GAME_NAME=8bit
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mkdir -p $TEMP_DIR
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rgbasm -Weverything -E -i $CODE_DIR -o $TEMP_DIR/$GAME_NAME.obj $CODE_DIR/main.asm
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rgblink -n $BUILD_DIR/$GAME_NAME.sym -m $BUILD_DIR/$GAME_NAME.map -o $BUILD_DIR/$GAME_NAME.gb $TEMP_DIR/$GAME_NAME.obj
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rgbfix -v -p0 $BUILD_DIR/$GAME_NAME.gb
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@ -0,0 +1,24 @@
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LED_OFF EQU $25
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LED_ON EQU $26
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CTRL_HT EQU 7
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CTRL_MI EQU 6
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CTRL_RI EQU 5
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CTRL_RO EQU 4
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CTRL_IO EQU 3
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CTRL_II EQU 2
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CTRL_AI EQU 1
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CTRL_AO EQU 0
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CTRL_EO EQU 7
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CTRL_SU EQU 6
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CTRL_BI EQU 5
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CTRL_OI EQU 4
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CTRL_CE EQU 3
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CTRL_CO EQU 2
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CTRL_JP EQU 1
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CTRL_FI EQU 0
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FLAG_C EQU 1
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FLAG_Z EQU 0
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@ -0,0 +1,913 @@
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;*
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;* Gameboy Hardware definitions
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;*
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;* Based on Jones' hardware.inc
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;* And based on Carsten Sorensen's ideas.
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;*
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;* Rev 1.1 - 15-Jul-97 : Added define check
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;* Rev 1.2 - 18-Jul-97 : Added revision check macro
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;* Rev 1.3 - 19-Jul-97 : Modified for RGBASM V1.05
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;* Rev 1.4 - 27-Jul-97 : Modified for new subroutine prefixes
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;* Rev 1.5 - 15-Aug-97 : Added _HRAM, PAD, CART defines
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;* : and Nintendo Logo
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;* Rev 1.6 - 30-Nov-97 : Added rDIV, rTIMA, rTMA, & rTAC
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;* Rev 1.7 - 31-Jan-98 : Added _SCRN0, _SCRN1
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;* Rev 1.8 - 15-Feb-98 : Added rSB, rSC
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;* Rev 1.9 - 16-Feb-98 : Converted I/O registers to $FFXX format
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;* Rev 2.0 - : Added GBC registers
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;* Rev 2.1 - : Added MBC5 & cart RAM enable/disable defines
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;* Rev 2.2 - : Fixed NR42,NR43, & NR44 equates
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;* Rev 2.3 - : Fixed incorrect _HRAM equate
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;* Rev 2.4 - 27-Apr-13 : Added some cart defines (AntonioND)
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;* Rev 2.5 - 03-May-15 : Fixed format (AntonioND)
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;* Rev 2.6 - 09-Apr-16 : Added GBC OAM and cart defines (AntonioND)
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;* Rev 2.7 - 19-Jan-19 : Added rPCMXX (ISSOtm)
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;* Rev 2.8 - 03-Feb-19 : Added audio registers flags (Álvaro Cuesta)
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;* Rev 2.9 - 28-Feb-20 : Added utility rP1 constants
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;* Rev 3.0 - 27-Aug-20 : Register ordering, byte-based sizes, OAM additions, general cleanup (Blitter Object)
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; If all of these are already defined, don't do it again.
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IF !DEF(HARDWARE_INC)
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HARDWARE_INC SET 1
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rev_Check_hardware_inc : MACRO
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;NOTE: REVISION NUMBER CHANGES MUST BE ADDED
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;TO SECOND PARAMETER IN FOLLOWING LINE.
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IF \1 > 3.0 ;PUT REVISION NUMBER HERE
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WARN "Version \1 or later of 'hardware.inc' is required."
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ENDC
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ENDM
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_VRAM EQU $8000 ; $8000->$9FFF
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_VRAM8000 EQU _VRAM
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_VRAM8800 EQU _VRAM+$800
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_VRAM9000 EQU _VRAM+$1000
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_SCRN0 EQU $9800 ; $9800->$9BFF
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_SCRN1 EQU $9C00 ; $9C00->$9FFF
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_SRAM EQU $A000 ; $A000->$BFFF
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_RAM EQU $C000 ; $C000->$CFFF / $C000->$DFFF
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_RAMBANK EQU $D000 ; $D000->$DFFF
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_OAMRAM EQU $FE00 ; $FE00->$FE9F
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_IO EQU $FF00 ; $FF00->$FF7F,$FFFF
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_AUD3WAVERAM EQU $FF30 ; $FF30->$FF3F
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_HRAM EQU $FF80 ; $FF80->$FFFE
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; *** MBC5 Equates ***
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rRAMG EQU $0000 ; $0000->$1fff
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rROMB0 EQU $2000 ; $2000->$2fff
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rROMB1 EQU $3000 ; $3000->$3fff - If more than 256 ROM banks are present.
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rRAMB EQU $4000 ; $4000->$5fff - Bit 3 enables rumble (if present)
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;***************************************************************************
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;*
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;* Custom registers
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;*
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;***************************************************************************
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; --
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; -- P1 ($FF00)
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; -- Register for reading joy pad info. (R/W)
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; --
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rP1 EQU $FF00
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P1F_5 EQU %00100000 ; P15 out port, set to 0 to get buttons
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P1F_4 EQU %00010000 ; P14 out port, set to 0 to get dpad
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P1F_3 EQU %00001000 ; P13 in port
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P1F_2 EQU %00000100 ; P12 in port
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P1F_1 EQU %00000010 ; P11 in port
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P1F_0 EQU %00000001 ; P10 in port
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P1F_GET_DPAD EQU P1F_5
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P1F_GET_BTN EQU P1F_4
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P1F_GET_NONE EQU P1F_4 | P1F_5
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; --
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; -- SB ($FF01)
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; -- Serial Transfer Data (R/W)
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; --
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rSB EQU $FF01
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; --
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; -- SC ($FF02)
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; -- Serial I/O Control (R/W)
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; --
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rSC EQU $FF02
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; --
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; -- DIV ($FF04)
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; -- Divider register (R/W)
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; --
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rDIV EQU $FF04
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; --
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; -- TIMA ($FF05)
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; -- Timer counter (R/W)
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; --
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rTIMA EQU $FF05
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; --
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; -- TMA ($FF06)
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; -- Timer modulo (R/W)
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; --
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rTMA EQU $FF06
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; --
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; -- TAC ($FF07)
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; -- Timer control (R/W)
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; --
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rTAC EQU $FF07
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TACF_START EQU %00000100
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TACF_STOP EQU %00000000
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TACF_4KHZ EQU %00000000
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TACF_16KHZ EQU %00000011
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TACF_65KHZ EQU %00000010
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TACF_262KHZ EQU %00000001
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; --
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; -- IF ($FF0F)
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; -- Interrupt Flag (R/W)
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; --
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rIF EQU $FF0F
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; --
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; -- AUD1SWEEP/NR10 ($FF10)
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; -- Sweep register (R/W)
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; --
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; -- Bit 6-4 - Sweep Time
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; -- Bit 3 - Sweep Increase/Decrease
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; -- 0: Addition (frequency increases???)
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; -- 1: Subtraction (frequency increases???)
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; -- Bit 2-0 - Number of sweep shift (# 0-7)
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; -- Sweep Time: (n*7.8ms)
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; --
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rNR10 EQU $FF10
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rAUD1SWEEP EQU rNR10
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AUD1SWEEP_UP EQU %00000000
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AUD1SWEEP_DOWN EQU %00001000
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; --
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; -- AUD1LEN/NR11 ($FF11)
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; -- Sound length/Wave pattern duty (R/W)
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; --
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; -- Bit 7-6 - Wave Pattern Duty (00:12.5% 01:25% 10:50% 11:75%)
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; -- Bit 5-0 - Sound length data (# 0-63)
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; --
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rNR11 EQU $FF11
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rAUD1LEN EQU rNR11
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; --
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; -- AUD1ENV/NR12 ($FF12)
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; -- Envelope (R/W)
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; --
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; -- Bit 7-4 - Initial value of envelope
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; -- Bit 3 - Envelope UP/DOWN
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; -- 0: Decrease
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; -- 1: Range of increase
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; -- Bit 2-0 - Number of envelope sweep (# 0-7)
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; --
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rNR12 EQU $FF12
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rAUD1ENV EQU rNR12
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; --
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; -- AUD1LOW/NR13 ($FF13)
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; -- Frequency low byte (W)
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; --
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rNR13 EQU $FF13
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rAUD1LOW EQU rNR13
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; --
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; -- AUD1HIGH/NR14 ($FF14)
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; -- Frequency high byte (W)
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; --
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; -- Bit 7 - Initial (when set, sound restarts)
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; -- Bit 6 - Counter/consecutive selection
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; -- Bit 2-0 - Frequency's higher 3 bits
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; --
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rNR14 EQU $FF14
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rAUD1HIGH EQU rNR14
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; --
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; -- AUD2LEN/NR21 ($FF16)
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; -- Sound Length; Wave Pattern Duty (R/W)
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; --
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; -- see AUD1LEN for info
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; --
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rNR21 EQU $FF16
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rAUD2LEN EQU rNR21
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; --
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; -- AUD2ENV/NR22 ($FF17)
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; -- Envelope (R/W)
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; --
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; -- see AUD1ENV for info
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; --
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rNR22 EQU $FF17
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rAUD2ENV EQU rNR22
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; --
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; -- AUD2LOW/NR23 ($FF18)
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; -- Frequency low byte (W)
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; --
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rNR23 EQU $FF18
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rAUD2LOW EQU rNR23
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; --
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; -- AUD2HIGH/NR24 ($FF19)
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; -- Frequency high byte (W)
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; --
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; -- see AUD1HIGH for info
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; --
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rNR24 EQU $FF19
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rAUD2HIGH EQU rNR24
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; --
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; -- AUD3ENA/NR30 ($FF1A)
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; -- Sound on/off (R/W)
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; --
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; -- Bit 7 - Sound ON/OFF (1=ON,0=OFF)
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; --
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rNR30 EQU $FF1A
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rAUD3ENA EQU rNR30
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; --
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; -- AUD3LEN/NR31 ($FF1B)
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; -- Sound length (R/W)
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; --
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; -- Bit 7-0 - Sound length
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; --
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rNR31 EQU $FF1B
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rAUD3LEN EQU rNR31
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; --
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; -- AUD3LEVEL/NR32 ($FF1C)
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; -- Select output level
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; --
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; -- Bit 6-5 - Select output level
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; -- 00: 0/1 (mute)
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; -- 01: 1/1
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; -- 10: 1/2
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; -- 11: 1/4
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; --
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rNR32 EQU $FF1C
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rAUD3LEVEL EQU rNR32
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; --
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||||
; -- AUD3LOW/NR33 ($FF1D)
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; -- Frequency low byte (W)
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; --
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; -- see AUD1LOW for info
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; --
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rNR33 EQU $FF1D
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rAUD3LOW EQU rNR33
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|
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; --
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; -- AUD3HIGH/NR34 ($FF1E)
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; -- Frequency high byte (W)
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; --
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; -- see AUD1HIGH for info
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; --
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rNR34 EQU $FF1E
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rAUD3HIGH EQU rNR34
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|
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; --
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; -- AUD4LEN/NR41 ($FF20)
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; -- Sound length (R/W)
|
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; --
|
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; -- Bit 5-0 - Sound length data (# 0-63)
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; --
|
||||
rNR41 EQU $FF20
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rAUD4LEN EQU rNR41
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||||
|
||||
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||||
; --
|
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; -- AUD4ENV/NR42 ($FF21)
|
||||
; -- Envelope (R/W)
|
||||
; --
|
||||
; -- see AUD1ENV for info
|
||||
; --
|
||||
rNR42 EQU $FF21
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rAUD4ENV EQU rNR42
|
||||
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||||
|
||||
; --
|
||||
; -- AUD4POLY/NR43 ($FF22)
|
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; -- Polynomial counter (R/W)
|
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; --
|
||||
; -- Bit 7-4 - Selection of the shift clock frequency of the (scf)
|
||||
; -- polynomial counter (0000-1101)
|
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; -- freq=drf*1/2^scf (not sure)
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; -- Bit 3 - Selection of the polynomial counter's step
|
||||
; -- 0: 15 steps
|
||||
; -- 1: 7 steps
|
||||
; -- Bit 2-0 - Selection of the dividing ratio of frequencies (drf)
|
||||
; -- 000: f/4 001: f/8 010: f/16 011: f/24
|
||||
; -- 100: f/32 101: f/40 110: f/48 111: f/56 (f=4.194304 Mhz)
|
||||
; --
|
||||
rNR43 EQU $FF22
|
||||
rAUD4POLY EQU rNR43
|
||||
|
||||
|
||||
; --
|
||||
; -- AUD4GO/NR44 ($FF23)
|
||||
; --
|
||||
; -- Bit 7 - Inital
|
||||
; -- Bit 6 - Counter/consecutive selection
|
||||
; --
|
||||
rNR44 EQU $FF23
|
||||
rAUD4GO EQU rNR44
|
||||
|
||||
|
||||
; --
|
||||
; -- AUDVOL/NR50 ($FF24)
|
||||
; -- Channel control / ON-OFF / Volume (R/W)
|
||||
; --
|
||||
; -- Bit 7 - Vin->SO2 ON/OFF (Vin??)
|
||||
; -- Bit 6-4 - SO2 output level (volume) (# 0-7)
|
||||
; -- Bit 3 - Vin->SO1 ON/OFF (Vin??)
|
||||
; -- Bit 2-0 - SO1 output level (volume) (# 0-7)
|
||||
; --
|
||||
rNR50 EQU $FF24
|
||||
rAUDVOL EQU rNR50
|
||||
|
||||
AUDVOL_VIN_LEFT EQU %10000000 ; SO2
|
||||
AUDVOL_VIN_RIGHT EQU %00001000 ; SO1
|
||||
|
||||
|
||||
; --
|
||||
; -- AUDTERM/NR51 ($FF25)
|
||||
; -- Selection of Sound output terminal (R/W)
|
||||
; --
|
||||
; -- Bit 7 - Output sound 4 to SO2 terminal
|
||||
; -- Bit 6 - Output sound 3 to SO2 terminal
|
||||
; -- Bit 5 - Output sound 2 to SO2 terminal
|
||||
; -- Bit 4 - Output sound 1 to SO2 terminal
|
||||
; -- Bit 3 - Output sound 4 to SO1 terminal
|
||||
; -- Bit 2 - Output sound 3 to SO1 terminal
|
||||
; -- Bit 1 - Output sound 2 to SO1 terminal
|
||||
; -- Bit 0 - Output sound 0 to SO1 terminal
|
||||
; --
|
||||
rNR51 EQU $FF25
|
||||
rAUDTERM EQU rNR51
|
||||
|
||||
; SO2
|
||||
AUDTERM_4_LEFT EQU %10000000
|
||||
AUDTERM_3_LEFT EQU %01000000
|
||||
AUDTERM_2_LEFT EQU %00100000
|
||||
AUDTERM_1_LEFT EQU %00010000
|
||||
; SO1
|
||||
AUDTERM_4_RIGHT EQU %00001000
|
||||
AUDTERM_3_RIGHT EQU %00000100
|
||||
AUDTERM_2_RIGHT EQU %00000010
|
||||
AUDTERM_1_RIGHT EQU %00000001
|
||||
|
||||
|
||||
; --
|
||||
; -- AUDENA/NR52 ($FF26)
|
||||
; -- Sound on/off (R/W)
|
||||
; --
|
||||
; -- Bit 7 - All sound on/off (sets all audio regs to 0!)
|
||||
; -- Bit 3 - Sound 4 ON flag (read only)
|
||||
; -- Bit 2 - Sound 3 ON flag (read only)
|
||||
; -- Bit 1 - Sound 2 ON flag (read only)
|
||||
; -- Bit 0 - Sound 1 ON flag (read only)
|
||||
; --
|
||||
rNR52 EQU $FF26
|
||||
rAUDENA EQU rNR52
|
||||
|
||||
AUDENA_ON EQU %10000000
|
||||
AUDENA_OFF EQU %00000000 ; sets all audio regs to 0!
|
||||
|
||||
|
||||
; --
|
||||
; -- LCDC ($FF40)
|
||||
; -- LCD Control (R/W)
|
||||
; --
|
||||
rLCDC EQU $FF40
|
||||
|
||||
LCDCF_OFF EQU %00000000 ; LCD Control Operation
|
||||
LCDCF_ON EQU %10000000 ; LCD Control Operation
|
||||
LCDCF_WIN9800 EQU %00000000 ; Window Tile Map Display Select
|
||||
LCDCF_WIN9C00 EQU %01000000 ; Window Tile Map Display Select
|
||||
LCDCF_WINOFF EQU %00000000 ; Window Display
|
||||
LCDCF_WINON EQU %00100000 ; Window Display
|
||||
LCDCF_BG8800 EQU %00000000 ; BG & Window Tile Data Select
|
||||
LCDCF_BG8000 EQU %00010000 ; BG & Window Tile Data Select
|
||||
LCDCF_BG9800 EQU %00000000 ; BG Tile Map Display Select
|
||||
LCDCF_BG9C00 EQU %00001000 ; BG Tile Map Display Select
|
||||
LCDCF_OBJ8 EQU %00000000 ; OBJ Construction
|
||||
LCDCF_OBJ16 EQU %00000100 ; OBJ Construction
|
||||
LCDCF_OBJOFF EQU %00000000 ; OBJ Display
|
||||
LCDCF_OBJON EQU %00000010 ; OBJ Display
|
||||
LCDCF_BGOFF EQU %00000000 ; BG Display
|
||||
LCDCF_BGON EQU %00000001 ; BG Display
|
||||
; "Window Character Data Select" follows BG
|
||||
|
||||
|
||||
; --
|
||||
; -- STAT ($FF41)
|
||||
; -- LCDC Status (R/W)
|
||||
; --
|
||||
rSTAT EQU $FF41
|
||||
|
||||
STATF_LYC EQU %01000000 ; LYC=LY Coincidence (Selectable)
|
||||
STATF_MODE10 EQU %00100000 ; Mode 10
|
||||
STATF_MODE01 EQU %00010000 ; Mode 01 (V-Blank)
|
||||
STATF_MODE00 EQU %00001000 ; Mode 00 (H-Blank)
|
||||
STATF_LYCF EQU %00000100 ; Coincidence Flag
|
||||
STATF_HBL EQU %00000000 ; H-Blank
|
||||
STATF_VBL EQU %00000001 ; V-Blank
|
||||
STATF_OAM EQU %00000010 ; OAM-RAM is used by system
|
||||
STATF_LCD EQU %00000011 ; Both OAM and VRAM used by system
|
||||
STATF_BUSY EQU %00000010 ; When set, VRAM access is unsafe
|
||||
|
||||
|
||||
; --
|
||||
; -- SCY ($FF42)
|
||||
; -- Scroll Y (R/W)
|
||||
; --
|
||||
rSCY EQU $FF42
|
||||
|
||||
|
||||
; --
|
||||
; -- SCX ($FF43)
|
||||
; -- Scroll X (R/W)
|
||||
; --
|
||||
rSCX EQU $FF43
|
||||
|
||||
|
||||
; --
|
||||
; -- LY ($FF44)
|
||||
; -- LCDC Y-Coordinate (R)
|
||||
; --
|
||||
; -- Values range from 0->153. 144->153 is the VBlank period.
|
||||
; --
|
||||
rLY EQU $FF44
|
||||
|
||||
|
||||
; --
|
||||
; -- LYC ($FF45)
|
||||
; -- LY Compare (R/W)
|
||||
; --
|
||||
; -- When LY==LYC, STATF_LYCF will be set in STAT
|
||||
; --
|
||||
rLYC EQU $FF45
|
||||
|
||||
|
||||
; --
|
||||
; -- DMA ($FF46)
|
||||
; -- DMA Transfer and Start Address (W)
|
||||
; --
|
||||
rDMA EQU $FF46
|
||||
|
||||
|
||||
; --
|
||||
; -- BGP ($FF47)
|
||||
; -- BG Palette Data (W)
|
||||
; --
|
||||
; -- Bit 7-6 - Intensity for %11
|
||||
; -- Bit 5-4 - Intensity for %10
|
||||
; -- Bit 3-2 - Intensity for %01
|
||||
; -- Bit 1-0 - Intensity for %00
|
||||
; --
|
||||
rBGP EQU $FF47
|
||||
|
||||
|
||||
; --
|
||||
; -- OBP0 ($FF48)
|
||||
; -- Object Palette 0 Data (W)
|
||||
; --
|
||||
; -- See BGP for info
|
||||
; --
|
||||
rOBP0 EQU $FF48
|
||||
|
||||
|
||||
; --
|
||||
; -- OBP1 ($FF49)
|
||||
; -- Object Palette 1 Data (W)
|
||||
; --
|
||||
; -- See BGP for info
|
||||
; --
|
||||
rOBP1 EQU $FF49
|
||||
|
||||
|
||||
; --
|
||||
; -- WY ($FF4A)
|
||||
; -- Window Y Position (R/W)
|
||||
; --
|
||||
; -- 0 <= WY <= 143
|
||||
; -- When WY = 0, the window is displayed from the top edge of the LCD screen.
|
||||
; --
|
||||
rWY EQU $FF4A
|
||||
|
||||
|
||||
; --
|
||||
; -- WX ($FF4B)
|
||||
; -- Window X Position (R/W)
|
||||
; --
|
||||
; -- 7 <= WX <= 166
|
||||
; -- When WX = 7, the window is displayed from the left edge of the LCD screen.
|
||||
; -- Values of 0-6 and 166 are unreliable due to hardware bugs.
|
||||
; --
|
||||
rWX EQU $FF4B
|
||||
|
||||
|
||||
; --
|
||||
; -- SPEED ($FF4D)
|
||||
; -- Select CPU Speed (R/W)
|
||||
; --
|
||||
rKEY1 EQU $FF4D
|
||||
rSPD EQU rKEY1
|
||||
|
||||
KEY1F_DBLSPEED EQU %10000000 ; 0=Normal Speed, 1=Double Speed (R)
|
||||
KEY1F_PREPARE EQU %00000001 ; 0=No, 1=Prepare (R/W)
|
||||
|
||||
|
||||
; --
|
||||
; -- VBK ($FF4F)
|
||||
; -- Select Video RAM Bank (R/W)
|
||||
; --
|
||||
; -- Bit 0 - Bank Specification (0: Specify Bank 0; 1: Specify Bank 1)
|
||||
; --
|
||||
rVBK EQU $FF4F
|
||||
|
||||
|
||||
; --
|
||||
; -- HDMA1 ($FF51)
|
||||
; -- High byte for Horizontal Blanking/General Purpose DMA source address (W)
|
||||
; -- CGB Mode Only
|
||||
; --
|
||||
rHDMA1 EQU $FF51
|
||||
|
||||
|
||||
; --
|
||||
; -- HDMA2 ($FF52)
|
||||
; -- Low byte for Horizontal Blanking/General Purpose DMA source address (W)
|
||||
; -- CGB Mode Only
|
||||
; --
|
||||
rHDMA2 EQU $FF52
|
||||
|
||||
|
||||
; --
|
||||
; -- HDMA3 ($FF53)
|
||||
; -- High byte for Horizontal Blanking/General Purpose DMA destination address (W)
|
||||
; -- CGB Mode Only
|
||||
; --
|
||||
rHDMA3 EQU $FF53
|
||||
|
||||
|
||||
; --
|
||||
; -- HDMA4 ($FF54)
|
||||
; -- Low byte for Horizontal Blanking/General Purpose DMA destination address (W)
|
||||
; -- CGB Mode Only
|
||||
; --
|
||||
rHDMA4 EQU $FF54
|
||||
|
||||
|
||||
; --
|
||||
; -- HDMA5 ($FF55)
|
||||
; -- Transfer length (in tiles minus 1)/mode/start for Horizontal Blanking, General Purpose DMA (R/W)
|
||||
; -- CGB Mode Only
|
||||
; --
|
||||
rHDMA5 EQU $FF55
|
||||
|
||||
HDMA5F_MODE_GP EQU %00000000 ; General Purpose DMA (W)
|
||||
HDMA5F_MODE_HBL EQU %10000000 ; HBlank DMA (W)
|
||||
|
||||
; -- Once DMA has started, use HDMA5F_BUSY to check when the transfer is complete
|
||||
HDMA5F_BUSY EQU %10000000 ; 0=Busy (DMA still in progress), 1=Transfer complete (R)
|
||||
|
||||
|
||||
; --
|
||||
; -- RP ($FF56)
|
||||
; -- Infrared Communications Port (R/W)
|
||||
; -- CGB Mode Only
|
||||
; --
|
||||
rRP EQU $FF56
|
||||
|
||||
RPF_ENREAD EQU %11000000
|
||||
RPF_DATAIN EQU %00000010 ; 0=Receiving IR Signal, 1=Normal
|
||||
RPF_WRITE_HI EQU %00000001
|
||||
RPF_WRITE_LO EQU %00000000
|
||||
|
||||
|
||||
; --
|
||||
; -- BCPS ($FF68)
|
||||
; -- Background Color Palette Specification (R/W)
|
||||
; --
|
||||
rBCPS EQU $FF68
|
||||
|
||||
BCPSF_AUTOINC EQU %10000000 ; Auto Increment (0=Disabled, 1=Increment after Writing)
|
||||
|
||||
|
||||
; --
|
||||
; -- BCPD ($FF69)
|
||||
; -- Background Color Palette Data (R/W)
|
||||
; --
|
||||
rBCPD EQU $FF69
|
||||
|
||||
|
||||
; --
|
||||
; -- OCPS ($FF6A)
|
||||
; -- Object Color Palette Specification (R/W)
|
||||
; --
|
||||
rOCPS EQU $FF6A
|
||||
|
||||
OCPSF_AUTOINC EQU %10000000 ; Auto Increment (0=Disabled, 1=Increment after Writing)
|
||||
|
||||
|
||||
; --
|
||||
; -- OCPD ($FF6B)
|
||||
; -- Object Color Palette Data (R/W)
|
||||
; --
|
||||
rOCPD EQU $FF6B
|
||||
|
||||
|
||||
; --
|
||||
; -- SMBK/SVBK ($FF70)
|
||||
; -- Select Main RAM Bank (R/W)
|
||||
; --
|
||||
; -- Bit 2-0 - Bank Specification (0,1: Specify Bank 1; 2-7: Specify Banks 2-7)
|
||||
; --
|
||||
rSVBK EQU $FF70
|
||||
rSMBK EQU rSVBK
|
||||
|
||||
|
||||
; --
|
||||
; -- PCM12 ($FF76)
|
||||
; -- Sound channel 1&2 PCM amplitude (R)
|
||||
; --
|
||||
; -- Bit 7-4 - Copy of sound channel 2's PCM amplitude
|
||||
; -- Bit 3-0 - Copy of sound channel 1's PCM amplitude
|
||||
; --
|
||||
rPCM12 EQU $FF76
|
||||
|
||||
|
||||
; --
|
||||
; -- PCM34 ($FF77)
|
||||
; -- Sound channel 3&4 PCM amplitude (R)
|
||||
; --
|
||||
; -- Bit 7-4 - Copy of sound channel 4's PCM amplitude
|
||||
; -- Bit 3-0 - Copy of sound channel 3's PCM amplitude
|
||||
; --
|
||||
rPCM34 EQU $FF77
|
||||
|
||||
|
||||
; --
|
||||
; -- IE ($FFFF)
|
||||
; -- Interrupt Enable (R/W)
|
||||
; --
|
||||
rIE EQU $FFFF
|
||||
|
||||
IEF_HILO EQU %00010000 ; Transition from High to Low of Pin number P10-P13
|
||||
IEF_SERIAL EQU %00001000 ; Serial I/O transfer end
|
||||
IEF_TIMER EQU %00000100 ; Timer Overflow
|
||||
IEF_LCDC EQU %00000010 ; LCDC (see STAT)
|
||||
IEF_VBLANK EQU %00000001 ; V-Blank
|
||||
|
||||
|
||||
;***************************************************************************
|
||||
;*
|
||||
;* Flags common to multiple sound channels
|
||||
;*
|
||||
;***************************************************************************
|
||||
|
||||
; --
|
||||
; -- Square wave duty cycle
|
||||
; --
|
||||
; -- Can be used with AUD1LEN and AUD2LEN
|
||||
; -- See AUD1LEN for more info
|
||||
; --
|
||||
AUDLEN_DUTY_12_5 EQU %00000000 ; 12.5%
|
||||
AUDLEN_DUTY_25 EQU %01000000 ; 25%
|
||||
AUDLEN_DUTY_50 EQU %10000000 ; 50%
|
||||
AUDLEN_DUTY_75 EQU %11000000 ; 75%
|
||||
|
||||
|
||||
; --
|
||||
; -- Audio envelope flags
|
||||
; --
|
||||
; -- Can be used with AUD1ENV, AUD2ENV, AUD4ENV
|
||||
; -- See AUD1ENV for more info
|
||||
; --
|
||||
AUDENV_UP EQU %00001000
|
||||
AUDENV_DOWN EQU %00000000
|
||||
|
||||
|
||||
; --
|
||||
; -- Audio trigger flags
|
||||
; --
|
||||
; -- Can be used with AUD1HIGH, AUD2HIGH, AUD3HIGH
|
||||
; -- See AUD1HIGH for more info
|
||||
; --
|
||||
|
||||
AUDHIGH_RESTART EQU %10000000
|
||||
AUDHIGH_LENGTH_ON EQU %01000000
|
||||
AUDHIGH_LENGTH_OFF EQU %00000000
|
||||
|
||||
|
||||
;***************************************************************************
|
||||
;*
|
||||
;* CPU values on bootup (a=type, b=qualifier)
|
||||
;*
|
||||
;***************************************************************************
|
||||
|
||||
BOOTUP_A_DMG EQU $01 ; Dot Matrix Game
|
||||
BOOTUP_A_CGB EQU $11 ; Color GameBoy
|
||||
BOOTUP_A_MGB EQU $FF ; Mini GameBoy (Pocket GameBoy)
|
||||
|
||||
; if a=BOOTUP_A_CGB, bit 0 in b can be checked to determine if real CGB or
|
||||
; other system running in GBC mode
|
||||
BOOTUP_B_CGB EQU %00000000
|
||||
BOOTUP_B_AGB EQU %00000001 ; GBA, GBA SP, Game Boy Player, or New GBA SP
|
||||
|
||||
|
||||
;***************************************************************************
|
||||
;*
|
||||
;* Cart related
|
||||
;*
|
||||
;***************************************************************************
|
||||
|
||||
; $0143 Color GameBoy compatibility code
|
||||
CART_COMPATIBLE_DMG EQU $00
|
||||
CART_COMPATIBLE_DMG_GBC EQU $80
|
||||
CART_COMPATIBLE_GBC EQU $C0
|
||||
|
||||
; $0146 GameBoy/Super GameBoy indicator
|
||||
CART_INDICATOR_GB EQU $00
|
||||
CART_INDICATOR_SGB EQU $03
|
||||
|
||||
; $0147 Cartridge type
|
||||
CART_ROM EQU $00
|
||||
CART_ROM_MBC1 EQU $01
|
||||
CART_ROM_MBC1_RAM EQU $02
|
||||
CART_ROM_MBC1_RAM_BAT EQU $03
|
||||
CART_ROM_MBC2 EQU $05
|
||||
CART_ROM_MBC2_BAT EQU $06
|
||||
CART_ROM_RAM EQU $08
|
||||
CART_ROM_RAM_BAT EQU $09
|
||||
CART_ROM_MMM01 EQU $0B
|
||||
CART_ROM_MMM01_RAM EQU $0C
|
||||
CART_ROM_MMM01_RAM_BAT EQU $0D
|
||||
CART_ROM_MBC3_BAT_RTC EQU $0F
|
||||
CART_ROM_MBC3_RAM_BAT_RTC EQU $10
|
||||
CART_ROM_MBC3 EQU $11
|
||||
CART_ROM_MBC3_RAM EQU $12
|
||||
CART_ROM_MBC3_RAM_BAT EQU $13
|
||||
CART_ROM_MBC5 EQU $19
|
||||
CART_ROM_MBC5_BAT EQU $1A
|
||||
CART_ROM_MBC5_RAM_BAT EQU $1B
|
||||
CART_ROM_MBC5_RUMBLE EQU $1C
|
||||
CART_ROM_MBC5_RAM_RUMBLE EQU $1D
|
||||
CART_ROM_MBC5_RAM_BAT_RUMBLE EQU $1E
|
||||
CART_ROM_MBC7_RAM_BAT_GYRO EQU $22
|
||||
CART_ROM_POCKET_CAMERA EQU $FC
|
||||
CART_ROM_BANDAI_TAMA5 EQU $FD
|
||||
CART_ROM_HUDSON_HUC3 EQU $FE
|
||||
CART_ROM_HUDSON_HUC1 EQU $FF
|
||||
|
||||
; $0148 ROM size
|
||||
; these are kilobytes
|
||||
CART_ROM_32KB EQU $00 ; 2 banks
|
||||
CART_ROM_64KB EQU $01 ; 4 banks
|
||||
CART_ROM_128KB EQU $02 ; 8 banks
|
||||
CART_ROM_256KB EQU $03 ; 16 banks
|
||||
CART_ROM_512KB EQU $04 ; 32 banks
|
||||
CART_ROM_1024KB EQU $05 ; 64 banks
|
||||
CART_ROM_2048KB EQU $06 ; 128 banks
|
||||
CART_ROM_4096KB EQU $07 ; 256 banks
|
||||
CART_ROM_8192KB EQU $08 ; 512 banks
|
||||
CART_ROM_1152KB EQU $52 ; 72 banks
|
||||
CART_ROM_1280KB EQU $53 ; 80 banks
|
||||
CART_ROM_1536KB EQU $54 ; 96 banks
|
||||
|
||||
; $0149 SRAM size
|
||||
; these are kilobytes
|
||||
CART_SRAM_NONE EQU 0
|
||||
CART_SRAM_2KB EQU 1 ; 1 incomplete bank
|
||||
CART_SRAM_8KB EQU 2 ; 1 bank
|
||||
CART_SRAM_32KB EQU 3 ; 4 banks
|
||||
CART_SRAM_128KB EQU 4 ; 16 banks
|
||||
|
||||
CART_SRAM_ENABLE EQU $0A
|
||||
CART_SRAM_DISABLE EQU $00
|
||||
|
||||
; $014A Destination code
|
||||
CART_DEST_JAPANESE EQU $00
|
||||
CART_DEST_NON_JAPANESE EQU $01
|
||||
|
||||
|
||||
;***************************************************************************
|
||||
;*
|
||||
;* Keypad related
|
||||
;*
|
||||
;***************************************************************************
|
||||
|
||||
PADF_DOWN EQU $80
|
||||
PADF_UP EQU $40
|
||||
PADF_LEFT EQU $20
|
||||
PADF_RIGHT EQU $10
|
||||
PADF_START EQU $08
|
||||
PADF_SELECT EQU $04
|
||||
PADF_B EQU $02
|
||||
PADF_A EQU $01
|
||||
|
||||
PADB_DOWN EQU $7
|
||||
PADB_UP EQU $6
|
||||
PADB_LEFT EQU $5
|
||||
PADB_RIGHT EQU $4
|
||||
PADB_START EQU $3
|
||||
PADB_SELECT EQU $2
|
||||
PADB_B EQU $1
|
||||
PADB_A EQU $0
|
||||
|
||||
|
||||
;***************************************************************************
|
||||
;*
|
||||
;* Screen related
|
||||
;*
|
||||
;***************************************************************************
|
||||
|
||||
SCRN_X EQU 160 ; Width of screen in pixels
|
||||
SCRN_Y EQU 144 ; Height of screen in pixels
|
||||
SCRN_X_B EQU 20 ; Width of screen in bytes
|
||||
SCRN_Y_B EQU 18 ; Height of screen in bytes
|
||||
|
||||
SCRN_VX EQU 256 ; Virtual width of screen in pixels
|
||||
SCRN_VY EQU 256 ; Virtual height of screen in pixels
|
||||
SCRN_VX_B EQU 32 ; Virtual width of screen in bytes
|
||||
SCRN_VY_B EQU 32 ; Virtual height of screen in bytes
|
||||
|
||||
|
||||
;***************************************************************************
|
||||
;*
|
||||
;* OAM related
|
||||
;*
|
||||
;***************************************************************************
|
||||
|
||||
; OAM attributes
|
||||
; each entry in OAM RAM is 4 bytes (sizeof_OAM_ATTRS)
|
||||
RSRESET
|
||||
OAMA_Y RB 1 ; y pos
|
||||
OAMA_X RB 1 ; x pos
|
||||
OAMA_TILEID RB 1 ; tile id
|
||||
OAMA_FLAGS RB 1 ; flags (see below)
|
||||
sizeof_OAM_ATTRS RB 0
|
||||
|
||||
OAM_COUNT EQU 40 ; number of OAM entries in OAM RAM
|
||||
|
||||
; flags
|
||||
OAMF_PRI EQU %10000000 ; Priority
|
||||
OAMF_YFLIP EQU %01000000 ; Y flip
|
||||
OAMF_XFLIP EQU %00100000 ; X flip
|
||||
OAMF_PAL0 EQU %00000000 ; Palette number; 0,1 (DMG)
|
||||
OAMF_PAL1 EQU %00010000 ; Palette number; 0,1 (DMG)
|
||||
OAMF_BANK0 EQU %00000000 ; Bank number; 0,1 (GBC)
|
||||
OAMF_BANK1 EQU %00001000 ; Bank number; 0,1 (GBC)
|
||||
|
||||
OAMF_PALMASK EQU %00000111 ; Palette (GBC)
|
||||
|
||||
OAMB_PRI EQU 7 ; Priority
|
||||
OAMB_YFLIP EQU 6 ; Y flip
|
||||
OAMB_XFLIP EQU 5 ; X flip
|
||||
OAMB_PAL1 EQU 4 ; Palette number; 0,1 (DMG)
|
||||
OAMB_BANK1 EQU 3 ; Bank number; 0,1 (GBC)
|
||||
|
||||
|
||||
;*
|
||||
;* Nintendo scrolling logo
|
||||
;* (Code won't work on a real GameBoy)
|
||||
;* (if next lines are altered.)
|
||||
NINTENDO_LOGO : MACRO
|
||||
DB $CE,$ED,$66,$66,$CC,$0D,$00,$0B,$03,$73,$00,$83,$00,$0C,$00,$0D
|
||||
DB $00,$08,$11,$1F,$88,$89,$00,$0E,$DC,$CC,$6E,$E6,$DD,$DD,$D9,$99
|
||||
DB $BB,$BB,$67,$63,$6E,$0E,$EC,$CC,$DD,$DC,$99,$9F,$BB,$B9,$33,$3E
|
||||
ENDM
|
||||
|
||||
ENDC ;HARDWARE_INC
|
|
@ -0,0 +1,731 @@
|
|||
include "hardware.inc"
|
||||
include "constants.inc"
|
||||
include "signals.asm"
|
||||
include "ops.asm"
|
||||
include "tick.asm"
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; Interrupt Vectors
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "Vblank", ROM0[$0040]
|
||||
jp UpdateTiles
|
||||
|
||||
SECTION "LCDC", ROM0[$0048]
|
||||
reti
|
||||
|
||||
SECTION "Timer", ROM0[$0050]
|
||||
jp Timer
|
||||
|
||||
SECTION "Serial", ROM0[$0058]
|
||||
reti
|
||||
|
||||
SECTION "Joypad", ROM0[$0060]
|
||||
reti
|
||||
|
||||
; Entry point
|
||||
SECTION "Entry", ROM0[$100]
|
||||
nop
|
||||
jp start
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; Header
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "Header",ROM0[$0104]
|
||||
|
||||
; Logo
|
||||
DB $CE,$ED,$66,$66,$CC,$0D,$00,$0B,$03,$73,$00,$83,$00,$0C,$00,$0D
|
||||
DB $00,$08,$11,$1F,$88,$89,$00,$0E,$DC,$CC,$6E,$E6,$DD,$DD,$D9,$99
|
||||
DB $BB,$BB,$67,$63,$6E,$0E,$EC,$CC,$DD,$DC,$99,$9F,$BB,$B9,$33,$3E
|
||||
|
||||
; ROM Details
|
||||
DB "8BIT00000000000" ; $134 - Title (exactly 15 characters)
|
||||
DB 0 ; $143 - GBC Functionality: No
|
||||
DB 0,0 ; $144 - Licensee code
|
||||
DB 0 ; $146 - SGB Support: No
|
||||
DB 0 ; $147 - Cart type: No MBC (32K ROM only)
|
||||
DB 0 ; $148 - ROM Size: 32K (No Banking)
|
||||
DB 0 ; $149 - External ram Size: None
|
||||
DB 1 ; $14a - Destination: Non-Japan
|
||||
DB $33 ; $14b - Old Licensee code: must be $33
|
||||
DB 0 ; $14c - Mask ROM version
|
||||
DB 0 ; $14d - Complement check (RGBDS will fill)
|
||||
DW 0 ; $14e - Checksum (RGBDS will fill)
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; Entry Point
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "Main", ROM0[$150]
|
||||
start:
|
||||
di
|
||||
ld SP, $FFFF
|
||||
|
||||
; Turn LCD off
|
||||
.wait_for_vblank
|
||||
ldh a, [rLY]
|
||||
cp 145
|
||||
jr nz, .wait_for_vblank
|
||||
ld a, [rLCDC]
|
||||
xor LCDCF_ON
|
||||
ld [rLCDC], a
|
||||
|
||||
; Load tiles into VRAM
|
||||
ld hl, _VRAM
|
||||
ld de, Tiles_Begin
|
||||
ld bc, Tiles_End-Tiles_Begin
|
||||
call CopyBytes
|
||||
|
||||
; Fill the map
|
||||
ld hl, _SCRN0
|
||||
ld de, TileMap_Begin
|
||||
ld bc, TileMap_End-TileMap_Begin
|
||||
call CopyBytes
|
||||
|
||||
; Set background palette
|
||||
ld a, %11100100
|
||||
ld [rBGP], a
|
||||
|
||||
; Turn LCD back on
|
||||
ld a, [rLCDC]
|
||||
or LCDCF_ON
|
||||
ld [rLCDC], a
|
||||
|
||||
; Set up timer and vblank interrupts
|
||||
ld a, IEF_TIMER | IEF_VBLANK
|
||||
ld [rIE], a
|
||||
|
||||
; Configure timer
|
||||
; TODO: Make this adjustable at runtime (clock speed adjust)
|
||||
ld a, TACF_4KHZ | TACF_START
|
||||
ld [rTAC], a
|
||||
xor a
|
||||
ld [rTMA], a
|
||||
|
||||
; Zero all state
|
||||
ld hl, StateBegin
|
||||
ld bc, StateEnd-StateBegin
|
||||
call SetByte
|
||||
|
||||
; Zero all values
|
||||
ld hl, DataBegin
|
||||
ld bc, DataEnd-DataBegin
|
||||
call SetByte
|
||||
|
||||
; Turn off all LEDs
|
||||
ld a, LED_OFF
|
||||
ld hl, LedBegin
|
||||
ld bc, LedEnd-LedBegin
|
||||
call SetByte
|
||||
|
||||
; Load the program
|
||||
; TODO: Make this programmable at runtime
|
||||
ld a, $e0
|
||||
ld [ram], a ; OUT
|
||||
ld a, $2f
|
||||
ld [ram+1], a ; ADD 15
|
||||
ld a, $74
|
||||
ld [ram+2], a ; JC 4
|
||||
ld a, $60
|
||||
ld [ram+3], a ; JMP 0
|
||||
ld a, $3f
|
||||
ld [ram+4], a ; SUB 15
|
||||
ld a, $e0
|
||||
ld [ram+5], a ; OUT
|
||||
ld a, $80
|
||||
ld [ram+6], a ; JZ 0
|
||||
ld a, $64
|
||||
ld [ram+7], a ; JMP 4
|
||||
xor a
|
||||
ld [ram+8], a ; NOP
|
||||
ld [ram+9], a ; NOP
|
||||
ld [ram+10], a ; NOP
|
||||
ld [ram+11], a ; NOP
|
||||
ld [ram+12], a ; NOP
|
||||
ld [ram+13], a ; NOP
|
||||
ld [ram+14], a ; NOP
|
||||
ld a, 15
|
||||
ld [ram+15], a ; Data
|
||||
|
||||
; Load default clock of 1Hz (16 timer interrupts)
|
||||
ld a, 2
|
||||
ld [clk], a
|
||||
ld a, 1
|
||||
ld [clk_div2], a
|
||||
|
||||
; Initialize as running
|
||||
ld a, 1
|
||||
ld [running], a
|
||||
|
||||
; Tick once before we begin to set the stage
|
||||
call Tick
|
||||
|
||||
ei
|
||||
|
||||
.loop
|
||||
halt
|
||||
nop
|
||||
|
||||
; If we aren't running, loop
|
||||
ld a, [running]
|
||||
cp 1
|
||||
jr nz, .loop
|
||||
|
||||
; Check for Button A state
|
||||
; State is only set once per press; no repeats
|
||||
call ReadKeys
|
||||
bit 0, a
|
||||
jr z, .key_released
|
||||
|
||||
.key_pressed:
|
||||
ld a, LED_ON
|
||||
ld [clk_led], a
|
||||
ld a, [button_state]
|
||||
cp 0
|
||||
jr z, .tick
|
||||
jr .loop
|
||||
|
||||
.key_released:
|
||||
xor a
|
||||
ld [button_state], a
|
||||
ld a, LED_OFF
|
||||
ld [clk_led], a
|
||||
jr .loop
|
||||
|
||||
.tick:
|
||||
; Key press = rising edge
|
||||
; Key release = falling edge
|
||||
ld a, 1
|
||||
ld [button_state], a
|
||||
call Tick
|
||||
jr .loop
|
||||
|
||||
|
||||
; [in] de: Source address
|
||||
; [in] hl: Destination address
|
||||
; [in] bc: Count
|
||||
CopyBytes:
|
||||
; Increment each by one to prevent rolling over when decrementing
|
||||
inc b
|
||||
inc c
|
||||
jr .skip
|
||||
|
||||
.loop:
|
||||
ld a, [de]
|
||||
ld [hl+], a
|
||||
inc de
|
||||
|
||||
.skip:
|
||||
dec c
|
||||
jr nz, .loop
|
||||
dec b
|
||||
jr nz, .loop
|
||||
|
||||
ret
|
||||
|
||||
|
||||
; [in] a: Byte to set
|
||||
; [in] hl: Destination address
|
||||
; [in] bc: Count
|
||||
SetByte:
|
||||
; Increment each by one to prevent rolling over when decrementing
|
||||
inc b
|
||||
inc c
|
||||
jr .skip
|
||||
|
||||
.loop
|
||||
ld [hl+], a
|
||||
|
||||
.skip:
|
||||
dec c
|
||||
jr nz, .loop
|
||||
dec b
|
||||
jr nz, .loop
|
||||
ret
|
||||
|
||||
; [out] a: x x x x start select b a
|
||||
ReadKeys:
|
||||
ld a, P1F_GET_BTN ;
|
||||
ld [rP1], a ; joypad info
|
||||
ld a, [rP1] ;
|
||||
ld a, [rP1] ; read twice to make sure
|
||||
and $0f ; low nibble contains buttons
|
||||
cpl ; low means pressed so we complement for logic purposes
|
||||
ret
|
||||
|
||||
|
||||
SECTION "Handlers", ROM0
|
||||
Timer:
|
||||
push af
|
||||
|
||||
ld a, [w_counter]
|
||||
add a, 1
|
||||
ld [w_counter], a
|
||||
ld hl, clk_div2
|
||||
cp [hl]
|
||||
jr z, .rising_edge
|
||||
ld hl, clk
|
||||
cp [hl]
|
||||
jr z, .falling_edge
|
||||
jr .exit
|
||||
|
||||
.rising_edge:
|
||||
ld a, LED_ON
|
||||
ld [clk_led], a
|
||||
call Tick
|
||||
jr .exit
|
||||
|
||||
.falling_edge:
|
||||
ld a, LED_OFF
|
||||
ld [clk_led], a
|
||||
xor a
|
||||
ld [w_counter], a
|
||||
|
||||
.exit:
|
||||
pop af
|
||||
reti
|
||||
|
||||
UpdateTiles:
|
||||
push af
|
||||
|
||||
; CLK
|
||||
ld hl, _SCRN0 + 4
|
||||
ld a, [clk_led]
|
||||
ld [hl], a
|
||||
|
||||
; PC
|
||||
ld hl, _SCRN0 + 13
|
||||
ld a, [pc_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [pc_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [pc_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [pc_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; OP
|
||||
ld hl, _SCRN0 + $040 + 14
|
||||
ld a, [opc_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [opc_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [opc_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; IR
|
||||
ld hl, _SCRN0 + $040 + 4
|
||||
ld a, [ir_led_7]
|
||||
ld [hl+], a
|
||||
ld a, [ir_led_6]
|
||||
ld [hl+], a
|
||||
ld a, [ir_led_5]
|
||||
ld [hl+], a
|
||||
ld a, [ir_led_4]
|
||||
ld [hl+], a
|
||||
ld a, [ir_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [ir_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [ir_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [ir_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; MAR
|
||||
ld hl, _SCRN0 + $080 + 4
|
||||
ld a, [mar_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [mar_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [mar_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [mar_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; BUS
|
||||
ld hl, _SCRN0 + $0A0 + 4
|
||||
ld a, [mem_led_7]
|
||||
ld [hl+], a
|
||||
ld a, [mem_led_6]
|
||||
ld [hl+], a
|
||||
ld a, [mem_led_5]
|
||||
ld [hl+], a
|
||||
ld a, [mem_led_4]
|
||||
ld [hl+], a
|
||||
ld a, [mem_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [mem_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [mem_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [mem_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; BUS
|
||||
ld hl, _SCRN0 + $0E0 + 4
|
||||
ld a, [bus_led_7]
|
||||
ld [hl+], a
|
||||
ld a, [bus_led_6]
|
||||
ld [hl+], a
|
||||
ld a, [bus_led_5]
|
||||
ld [hl+], a
|
||||
ld a, [bus_led_4]
|
||||
ld [hl+], a
|
||||
ld a, [bus_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [bus_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [bus_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [bus_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; A
|
||||
ld hl, _SCRN0 + $120 + 4
|
||||
ld a, [a_led_7]
|
||||
ld [hl+], a
|
||||
ld a, [a_led_6]
|
||||
ld [hl+], a
|
||||
ld a, [a_led_5]
|
||||
ld [hl+], a
|
||||
ld a, [a_led_4]
|
||||
ld [hl+], a
|
||||
ld a, [a_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [a_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [a_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [a_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; B
|
||||
ld hl, _SCRN0 + $140 + 4
|
||||
ld a, [b_led_7]
|
||||
ld [hl+], a
|
||||
ld a, [b_led_6]
|
||||
ld [hl+], a
|
||||
ld a, [b_led_5]
|
||||
ld [hl+], a
|
||||
ld a, [b_led_4]
|
||||
ld [hl+], a
|
||||
ld a, [b_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [b_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [b_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [b_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; ALU
|
||||
ld hl, _SCRN0 + $160 + 4
|
||||
ld a, [alu_led_7]
|
||||
ld [hl+], a
|
||||
ld a, [alu_led_6]
|
||||
ld [hl+], a
|
||||
ld a, [alu_led_5]
|
||||
ld [hl+], a
|
||||
ld a, [alu_led_4]
|
||||
ld [hl+], a
|
||||
ld a, [alu_led_3]
|
||||
ld [hl+], a
|
||||
ld a, [alu_led_2]
|
||||
ld [hl+], a
|
||||
ld a, [alu_led_1]
|
||||
ld [hl+], a
|
||||
ld a, [alu_led_0]
|
||||
ld [hl], a
|
||||
|
||||
; CTRL
|
||||
ld hl, _SCRN0 + $1A0 + 4
|
||||
ld a, [ctrl_led_ht]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_mi]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_ri]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_ro]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_io]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_ii]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_ai]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_ao]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_eo]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_su]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_bi]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_oi]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_ce]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_co]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_jp]
|
||||
ld [hl+], a
|
||||
ld a, [ctrl_led_fi]
|
||||
ld [hl], a
|
||||
|
||||
; Flags
|
||||
ld hl, _SCRN0 + $160 + 13
|
||||
ld a, [flag_led_c]
|
||||
ld [hl+], a
|
||||
ld a, [flag_led_z]
|
||||
ld [hl], a
|
||||
|
||||
; OUT
|
||||
ld hl, _SCRN0 + $220 + 4
|
||||
; 100s
|
||||
ld a, [display]
|
||||
add a, $1 ; $1 = tile id of 0
|
||||
ld [hl+], a
|
||||
; 10s
|
||||
ld a, [display+1]
|
||||
add a, $1
|
||||
ld [hl+], a
|
||||
; 1s
|
||||
ld a, [display+2]
|
||||
add a, $1
|
||||
ld [hl], a
|
||||
|
||||
.exit
|
||||
pop af
|
||||
reti
|
||||
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; Tile Data
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "Tile Data", ROM0
|
||||
|
||||
Tiles_Begin:
|
||||
DB $FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF,$FF ; Blank ($00)
|
||||
DB $83,$83,$7D,$7D,$6D,$6D,$6D,$6D,$6D,$6D,$7D,$7D,$83,$83,$FF,$FF ; 0 ($01)
|
||||
DB $EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$FF,$FF ; 1 ($02)
|
||||
DB $07,$07,$FB,$FB,$FB,$FB,$87,$87,$7F,$7F,$7F,$7F,$03,$03,$FF,$FF ; 2 ($03)
|
||||
DB $03,$03,$FD,$FD,$FD,$FD,$83,$83,$FD,$FD,$FD,$FD,$03,$03,$FF,$FF ; 3 ($04)
|
||||
DB $7D,$7D,$7D,$7D,$7D,$7D,$81,$81,$FD,$FD,$FD,$FD,$FD,$FD,$FF,$FF ; 4 ($05)
|
||||
DB $03,$03,$7F,$7F,$7F,$7F,$07,$07,$FB,$FB,$FB,$FB,$07,$07,$FF,$FF ; 5 ($06)
|
||||
DB $83,$83,$7F,$7F,$7F,$7F,$03,$03,$7D,$7D,$7D,$7D,$83,$83,$FF,$FF ; 6 ($07)
|
||||
DB $01,$01,$FD,$FD,$FD,$FD,$FD,$FD,$FD,$FD,$FD,$FD,$FD,$FD,$FF,$FF ; 7 ($08)
|
||||
DB $83,$83,$7D,$7D,$7D,$7D,$83,$83,$7D,$7D,$7D,$7D,$83,$83,$FF,$FF ; 8 ($09)
|
||||
DB $83,$83,$7D,$7D,$7D,$7D,$81,$81,$FD,$FD,$FD,$FD,$FD,$FD,$FF,$FF ; 9 ($0A)
|
||||
DB $C7,$C7,$BB,$BB,$7D,$7D,$7D,$7D,$01,$01,$7D,$7D,$7D,$7D,$FF,$FF ; A ($0B)
|
||||
DB $03,$03,$7D,$7D,$7D,$7D,$03,$03,$7D,$7D,$7D,$7D,$03,$03,$FF,$FF ; B ($0C)
|
||||
DB $83,$83,$7D,$7D,$7F,$7F,$7F,$7F,$7F,$7F,$7D,$7D,$83,$83,$FF,$FF ; C ($0D)
|
||||
DB $03,$03,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$03,$03,$FF,$FF ; D ($0E)
|
||||
DB $83,$83,$7F,$7F,$7F,$7F,$07,$07,$7F,$7F,$7F,$7F,$83,$83,$FF,$FF ; E ($0F)
|
||||
DB $01,$01,$7F,$7F,$7F,$7F,$03,$03,$7F,$7F,$7F,$7F,$7F,$7F,$FF,$FF ; F ($10)
|
||||
DB $83,$83,$7D,$7D,$7F,$7F,$61,$61,$7D,$7D,$7D,$7D,$83,$83,$FF,$FF ; G ($11)
|
||||
DB $7D,$7D,$7D,$7D,$7D,$7D,$01,$01,$7D,$7D,$7D,$7D,$7D,$7D,$FF,$FF ; H ($12)
|
||||
DB $01,$01,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$01,$01,$FF,$FF ; I ($13)
|
||||
DB $01,$01,$F7,$F7,$F7,$F7,$F7,$F7,$77,$77,$77,$77,$8F,$8F,$FF,$FF ; J ($14)
|
||||
DB $7B,$7B,$7B,$7B,$7B,$7B,$07,$07,$7B,$7B,$7B,$7B,$7B,$7B,$FF,$FF ; K ($15)
|
||||
DB $7F,$7F,$7F,$7F,$7F,$7F,$7F,$7F,$7F,$7F,$7F,$7F,$03,$03,$FF,$FF ; L ($16)
|
||||
DB $BB,$BB,$55,$55,$6D,$6D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$FF,$FF ; M ($17)
|
||||
DB $03,$03,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$FF,$FF ; N ($18)
|
||||
DB $83,$83,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$83,$83,$FF,$FF ; O ($19)
|
||||
DB $03,$03,$7D,$7D,$7D,$7D,$03,$03,$7F,$7F,$7F,$7F,$7F,$7F,$FF,$FF ; P ($1A)
|
||||
DB $83,$83,$7D,$7D,$7D,$7D,$7D,$7D,$75,$75,$7B,$7B,$85,$85,$FF,$FF ; Q ($1B)
|
||||
DB $83,$83,$7D,$7D,$7D,$7D,$03,$03,$7D,$7D,$7D,$7D,$7D,$7D,$FF,$FF ; R ($1C)
|
||||
DB $81,$81,$7F,$7F,$7F,$7F,$83,$83,$FD,$FD,$FD,$FD,$03,$03,$FF,$FF ; S ($1D)
|
||||
DB $01,$01,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$EF,$FF,$FF ; T ($1E)
|
||||
DB $7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$83,$83,$FF,$FF ; U ($1F)
|
||||
DB $7D,$7D,$7D,$7D,$BB,$BB,$BB,$BB,$D7,$D7,$D7,$D7,$EF,$EF,$FF,$FF ; V ($20)
|
||||
DB $7D,$7D,$7D,$7D,$7D,$7D,$7D,$7D,$6D,$6D,$55,$55,$BB,$BB,$FF,$FF ; W ($21)
|
||||
DB $7D,$7D,$BB,$BB,$D7,$D7,$EF,$EF,$D7,$D7,$BB,$BB,$7D,$7D,$FF,$FF ; X ($22)
|
||||
DB $7D,$7D,$7D,$7D,$BB,$BB,$D7,$D7,$EF,$EF,$EF,$EF,$EF,$EF,$FF,$FF ; Y ($23)
|
||||
DB $01,$01,$FD,$FD,$FB,$FB,$C7,$C7,$BF,$BF,$7F,$7F,$01,$01,$FF,$FF ; Z ($24)
|
||||
DB $FF,$83,$83,$7D,$83,$7D,$83,$7D,$83,$7D,$83,$7D,$FF,$83,$FF,$FF ; LED Off ($25)
|
||||
DB $FF,$83,$83,$01,$83,$01,$83,$01,$83,$01,$83,$01,$FF,$83,$FF,$FF ; LED On ($26)
|
||||
Tiles_End:
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; Tile Map
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "Tile Map", ROM0
|
||||
|
||||
TileMap_Begin:
|
||||
DB $0D,$16,$15,$00,$25,$00,$00,$00,$00,$00,$00,$00,$00,$25,$25,$25,$25,$00,$1A,$0D, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$000] CLK PC
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$020]
|
||||
DB $00,$13,$1C,$00,$25,$25,$25,$25,$25,$25,$25,$25,$00,$00,$25,$25,$25,$00,$19,$1A, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$040] IR OP
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$060]
|
||||
DB $17,$0B,$1C,$00,$25,$25,$25,$25,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$080] MAR
|
||||
DB $17,$0F,$17,$00,$25,$25,$25,$25,$25,$25,$25,$25,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$0A0] MEM
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$0C0]
|
||||
DB $0C,$1F,$1D,$00,$25,$25,$25,$25,$25,$25,$25,$25,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$0E0] BUS
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$100]
|
||||
DB $00,$00,$0B,$00,$25,$25,$25,$25,$25,$25,$25,$25,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$120] A
|
||||
DB $00,$00,$0C,$00,$25,$25,$25,$25,$25,$25,$25,$25,$00,$0D,$24,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$140] B C Z
|
||||
DB $0B,$16,$1F,$00,$25,$25,$25,$25,$25,$25,$25,$25,$00,$25,$25,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$160] ALU x x
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$080]
|
||||
DB $0D,$1E,$16,$00,$25,$25,$25,$25,$25,$25,$25,$25,$25,$25,$25,$25,$25,$25,$25,$25, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$1A0] CTL
|
||||
DB $00,$00,$00,$00,$12,$17,$1C,$1C,$13,$13,$0B,$0B,$0F,$1D,$0C,$19,$0D,$0D,$14,$10, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$1C0] H M R R I I A A E S B O C C J F
|
||||
DB $00,$00,$00,$00,$1E,$13,$13,$19,$19,$13,$13,$19,$19,$1F,$13,$13,$0F,$19,$1A,$13, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$1E0] T I I O O I I O O U I I E O P I
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$200]
|
||||
DB $19,$1F,$1E,$00,$01,$01,$01,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 ; [$220] OUT
|
||||
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
DB $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00, $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
|
||||
TileMap_End:
|
||||
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; State
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "State", WRAM0
|
||||
|
||||
StateBegin:
|
||||
|
||||
w_counter: DS 1
|
||||
clk: DS 1
|
||||
clk_div2: DS 1
|
||||
button_state: DS 1
|
||||
running: DS 1
|
||||
flags_temp: DS 1
|
||||
|
||||
StateEnd:
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; Data
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "Data", WRAM0
|
||||
|
||||
DataBegin:
|
||||
|
||||
bus: DS 1 ; 8 bit
|
||||
mar: DS 1 ; 4 bit
|
||||
mem: DS 1 ; 8 bit
|
||||
ir: DS 1 ; 8 bit
|
||||
pc: DS 1 ; 4 bit
|
||||
opc: DS 1 ; 3 bit
|
||||
a_reg: DS 1 ; 8 bit
|
||||
b_reg: DS 1 ; 8 bit
|
||||
alu: DS 1 ; 8 bit
|
||||
out_reg: DS 1 ; 8 bit
|
||||
ctrl: DS 2 ; ht | mi | ri | ro | io | ii | ai | ao || eo | su | bi | oi | ce | co | jp | fi
|
||||
flags: DS 1 ; c | z
|
||||
ram: DS 16
|
||||
|
||||
DataEnd:
|
||||
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
; LEDs
|
||||
; --------------------------------------------------------------------------------------------------------------------
|
||||
SECTION "LEDs", WRAM0
|
||||
|
||||
LedBegin:
|
||||
|
||||
clk_led: DS 1
|
||||
|
||||
bus_led_7: DS 1
|
||||
bus_led_6: DS 1
|
||||
bus_led_5: DS 1
|
||||
bus_led_4: DS 1
|
||||
bus_led_3: DS 1
|
||||
bus_led_2: DS 1
|
||||
bus_led_1: DS 1
|
||||
bus_led_0: DS 1
|
||||
|
||||
mar_led_3: DS 1
|
||||
mar_led_2: DS 1
|
||||
mar_led_1: DS 1
|
||||
mar_led_0: DS 1
|
||||
|
||||
mem_led_7: DS 1
|
||||
mem_led_6: DS 1
|
||||
mem_led_5: DS 1
|
||||
mem_led_4: DS 1
|
||||
mem_led_3: DS 1
|
||||
mem_led_2: DS 1
|
||||
mem_led_1: DS 1
|
||||
mem_led_0: DS 1
|
||||
|
||||
opc_led_2: DS 1
|
||||
opc_led_1: DS 1
|
||||
opc_led_0: DS 1
|
||||
|
||||
pc_led_3: DS 1
|
||||
pc_led_2: DS 1
|
||||
pc_led_1: DS 1
|
||||
pc_led_0: DS 1
|
||||
|
||||
ir_led_7: DS 1
|
||||
ir_led_6: DS 1
|
||||
ir_led_5: DS 1
|
||||
ir_led_4: DS 1
|
||||
ir_led_3: DS 1
|
||||
ir_led_2: DS 1
|
||||
ir_led_1: DS 1
|
||||
ir_led_0: DS 1
|
||||
|
||||
a_led_7: DS 1
|
||||
a_led_6: DS 1
|
||||
a_led_5: DS 1
|
||||
a_led_4: DS 1
|
||||
a_led_3: DS 1
|
||||
a_led_2: DS 1
|
||||
a_led_1: DS 1
|
||||
a_led_0: DS 1
|
||||
|
||||
b_led_7: DS 1
|
||||
b_led_6: DS 1
|
||||
b_led_5: DS 1
|
||||
b_led_4: DS 1
|
||||
b_led_3: DS 1
|
||||
b_led_2: DS 1
|
||||
b_led_1: DS 1
|
||||
b_led_0: DS 1
|
||||
|
||||
alu_led_7: DS 1
|
||||
alu_led_6: DS 1
|
||||
alu_led_5: DS 1
|
||||
alu_led_4: DS 1
|
||||
alu_led_3: DS 1
|
||||
alu_led_2: DS 1
|
||||
alu_led_1: DS 1
|
||||
alu_led_0: DS 1
|
||||
|
||||
ctrl_led_ht: DS 1
|
||||
ctrl_led_mi: DS 1
|
||||
ctrl_led_ri: DS 1
|
||||
ctrl_led_ro: DS 1
|
||||
ctrl_led_io: DS 1
|
||||
ctrl_led_ii: DS 1
|
||||
ctrl_led_ai: DS 1
|
||||
ctrl_led_ao: DS 1
|
||||
|
||||
ctrl_led_eo: DS 1
|
||||
ctrl_led_su: DS 1
|
||||
ctrl_led_bi: DS 1
|
||||
ctrl_led_oi: DS 1
|
||||
ctrl_led_ce: DS 1
|
||||
ctrl_led_co: DS 1
|
||||
ctrl_led_jp: DS 1
|
||||
ctrl_led_fi: DS 1
|
||||
|
||||
flag_led_c: DS 1
|
||||
flag_led_z: DS 1
|
||||
|
||||
display: DS 3 ; 3 digits
|
||||
|
||||
LedEnd:
|
||||
|
|
@ -0,0 +1,259 @@
|
|||
SECTION "Operations", ROM0
|
||||
|
||||
; For all instructions, b contains the current op stage
|
||||
|
||||
; [in] a: instruction
|
||||
; [in] b: stage index
|
||||
; 0b0000
|
||||
op_hlt:
|
||||
ld c, a
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr nz, .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_HT, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; 0b0001
|
||||
op_lda:
|
||||
ld c, a
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr z, .stage_2
|
||||
cp 3
|
||||
jr z, .stage_3
|
||||
jr .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_MI, [hl]
|
||||
set CTRL_IO, [hl]
|
||||
jr .exit
|
||||
|
||||
.stage_3:
|
||||
ld hl, ctrl
|
||||
set CTRL_RO, [hl]
|
||||
set CTRL_AI, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; 0b0010
|
||||
op_add:
|
||||
ld c, a
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr z, .stage_2
|
||||
cp 3
|
||||
jr z, .stage_3
|
||||
cp 4
|
||||
jr z, .stage_4
|
||||
jr .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_MI, [hl]
|
||||
set CTRL_IO, [hl]
|
||||
jr .exit
|
||||
|
||||
.stage_3:
|
||||
ld hl, ctrl
|
||||
set CTRL_RO, [hl]
|
||||
inc hl
|
||||
set CTRL_BI, [hl]
|
||||
jr .exit
|
||||
|
||||
.stage_4:
|
||||
ld hl, ctrl
|
||||
set CTRL_AI, [hl]
|
||||
inc hl
|
||||
set CTRL_EO, [hl]
|
||||
set CTRL_FI, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; 0b0011
|
||||
op_sub:
|
||||
ld c, a
|
||||
ld a, b
|
||||
cp 2
|
||||
jr z, .stage_2
|
||||
cp 3
|
||||
jr z, .stage_3
|
||||
cp 4
|
||||
jr z, .stage_4
|
||||
jr .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_MI, [hl]
|
||||
set CTRL_IO, [hl]
|
||||
jr .exit
|
||||
|
||||
.stage_3:
|
||||
ld hl, ctrl
|
||||
set CTRL_RO, [hl]
|
||||
inc hl
|
||||
set CTRL_BI, [hl]
|
||||
jr .exit
|
||||
|
||||
.stage_4:
|
||||
ld hl, ctrl
|
||||
set CTRL_AI, [hl]
|
||||
inc hl
|
||||
set CTRL_EO, [hl]
|
||||
set CTRL_SU, [hl]
|
||||
set CTRL_FI, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; 0b0100
|
||||
op_sta:
|
||||
ld c, a
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr z, .stage_2
|
||||
cp 3
|
||||
jr z, .stage_3
|
||||
jr .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_MI, [hl]
|
||||
set CTRL_IO, [hl]
|
||||
jr .exit
|
||||
|
||||
.stage_3:
|
||||
ld hl, ctrl
|
||||
set CTRL_AO, [hl]
|
||||
set CTRL_RI, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; 0b0101
|
||||
op_ldi:
|
||||
ld c, a
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr nz, .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_IO, [hl]
|
||||
set CTRL_AI, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; 0b0110
|
||||
op_jmp:
|
||||
ld c, a
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr nz, .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_IO, [hl]
|
||||
inc hl
|
||||
set CTRL_JP, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; [in] a: instruction
|
||||
; [in] b: stage index
|
||||
; 0b0111
|
||||
op_jc:
|
||||
ld c, a ; save instruction
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr nz, .exit
|
||||
|
||||
.stage_2:
|
||||
; save stage index
|
||||
ld d, a
|
||||
|
||||
ld hl, ctrl
|
||||
set CTRL_IO, [hl]
|
||||
inc hl
|
||||
|
||||
ld a, [flags]
|
||||
bit FLAG_C, a
|
||||
jr z, .exit
|
||||
set CTRL_JP, [hl]
|
||||
|
||||
.exit:
|
||||
; restore stage index
|
||||
ld a, d
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; [in] a: instruction
|
||||
; [in] b: stage index
|
||||
; 0b1000
|
||||
op_jz:
|
||||
ld c, a ; save instruction
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr nz, .exit
|
||||
|
||||
.stage_2:
|
||||
; save stage index
|
||||
ld d, a
|
||||
|
||||
ld hl, ctrl
|
||||
set CTRL_IO, [hl]
|
||||
inc hl
|
||||
|
||||
ld a, [flags]
|
||||
bit FLAG_Z, a
|
||||
jr z, .exit
|
||||
set CTRL_JP, [hl]
|
||||
|
||||
.exit:
|
||||
; restore stage index
|
||||
ld a, d
|
||||
ld c, a
|
||||
ret
|
||||
|
||||
; 0b1111
|
||||
op_out:
|
||||
ld c, a
|
||||
ld a, b
|
||||
|
||||
cp 2
|
||||
jr nz, .exit
|
||||
|
||||
.stage_2:
|
||||
ld hl, ctrl
|
||||
set CTRL_AO, [hl]
|
||||
inc hl
|
||||
set CTRL_OI, [hl]
|
||||
|
||||
.exit:
|
||||
ld c, a
|
||||
ret
|
||||
|
|
@ -0,0 +1,254 @@
|
|||
SECTION "Control Signals", ROM0
|
||||
|
||||
; [in] f: flags set from a previous operation
|
||||
UpdateFlags:
|
||||
ld hl, flags_temp
|
||||
|
||||
.check_z:
|
||||
jr z, .set_z
|
||||
res FLAG_Z, [hl]
|
||||
|
||||
.check_c:
|
||||
jr c, .set_c
|
||||
res FLAG_C, [hl]
|
||||
jr .exit
|
||||
|
||||
.set_z:
|
||||
set FLAG_Z, [hl]
|
||||
jr .check_c
|
||||
|
||||
.set_c:
|
||||
set FLAG_C, [hl]
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
|
||||
ctrl_ht:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_HT, b
|
||||
jr z, .exit
|
||||
|
||||
xor a
|
||||
ld [running], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_ro:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_RO, b
|
||||
jr z, .exit
|
||||
|
||||
; get memory offset based on MAR
|
||||
ld hl, ram
|
||||
ld a, [mar]
|
||||
add l
|
||||
ld l, a
|
||||
|
||||
ld a, [hl]
|
||||
ld [bus], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_io:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_IO, b
|
||||
jr z, .exit
|
||||
|
||||
ld a, [ir]
|
||||
and $0f
|
||||
ld [bus], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_ao:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_AO, b
|
||||
jr z, .exit
|
||||
|
||||
ld a, [a_reg]
|
||||
ld [bus], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_eo:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_EO, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [alu]
|
||||
ld [bus], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_co:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_CO, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [pc]
|
||||
ld [bus], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_mi:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_MI, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [bus]
|
||||
ld [mar], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_ri:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_RI, b
|
||||
jp z, .exit
|
||||
|
||||
; get memory offset based on MAR
|
||||
ld hl, ram
|
||||
ld a, [mar]
|
||||
add l
|
||||
ld l, a
|
||||
|
||||
ld a, [bus]
|
||||
ld [hl], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_ii:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_II, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [bus]
|
||||
ld [ir], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_ai:
|
||||
ld a, [ctrl]
|
||||
ld b, a
|
||||
bit CTRL_AI, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [bus]
|
||||
ld [a_reg], a
|
||||
; alu value reflects any change to A or B
|
||||
ld d, a
|
||||
ld a, [b_reg]
|
||||
add d
|
||||
ld [alu], a
|
||||
|
||||
call UpdateFlags
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_su:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_SU, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [b_reg]
|
||||
cpl
|
||||
inc a
|
||||
ld [b_reg], a
|
||||
; alu value reflects any change to A or B
|
||||
ld d, a
|
||||
ld a, [a_reg]
|
||||
add d
|
||||
ld [alu], a
|
||||
|
||||
call UpdateFlags
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_bi:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_BI, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [bus]
|
||||
ld [b_reg], a
|
||||
; alu value reflects any change to A or B
|
||||
ld d, a
|
||||
ld a, [a_reg]
|
||||
add d
|
||||
ld [alu], a
|
||||
|
||||
call UpdateFlags
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_oi:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_OI, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [bus]
|
||||
ld [out_reg], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_ce:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_CE, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [pc]
|
||||
inc a
|
||||
ld [pc], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_jp:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_JP, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [bus]
|
||||
ld [pc], a
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
ctrl_fi:
|
||||
ld a, [ctrl+1]
|
||||
ld b, a
|
||||
bit CTRL_FI, b
|
||||
jp z, .exit
|
||||
|
||||
ld a, [flags_temp]
|
||||
ld [flags], a
|
||||
|
||||
.exit:
|
||||
ret
|
|
@ -0,0 +1,294 @@
|
|||
; [in] a: value to calculate
|
||||
; [out] e: 100s place
|
||||
; [out] c: 10s place
|
||||
; [out] d: 1s place
|
||||
CalculateBCD:
|
||||
ld e, 0 ; count (100s place)
|
||||
|
||||
ld b, 100
|
||||
.sub_led_100:
|
||||
ld h, a ; save for 10s calc
|
||||
sub b
|
||||
jr c, .reset
|
||||
; count++
|
||||
ld c, a
|
||||
ld a, e
|
||||
inc a
|
||||
ld e, a
|
||||
ld a, c
|
||||
jr .sub_led_100
|
||||
.reset:
|
||||
ld b, 10
|
||||
ld c, 0 ; count (10s place)
|
||||
ld a, h
|
||||
.sub_led_10:
|
||||
sub b
|
||||
jr c, .mod
|
||||
; count++
|
||||
ld d, a
|
||||
ld a, c
|
||||
inc a
|
||||
ld c, a
|
||||
ld a, d
|
||||
jr .sub_led_10
|
||||
.mod:
|
||||
; a contains overflow; difference is remainder ($ff-remainder-9)
|
||||
ld b, a
|
||||
ld a, $ff
|
||||
sub b
|
||||
ld b, a
|
||||
ld a, 9
|
||||
sub b
|
||||
; 1s place
|
||||
ld d, a
|
||||
ret
|
||||
|
||||
; [in] a: Value to LED-ify
|
||||
; [in] hl: Start address of LED tile
|
||||
; [in] c: LED count
|
||||
UpdateLeds:
|
||||
ld b, a ; cached A
|
||||
dec hl ; pre-decrement, will be added back first way around the loop
|
||||
ld de, $00FF ; offset from HL (inc e will overflow to 0 for first offset)
|
||||
|
||||
; shift left for anything less than a count of 8 so we have MSB in the right spot for left shift
|
||||
ld a, 8
|
||||
sub c
|
||||
jr z, .check
|
||||
|
||||
.shift:
|
||||
sla b
|
||||
dec a
|
||||
jr nz, .shift
|
||||
|
||||
.check:
|
||||
inc hl
|
||||
|
||||
; determine if we've checked all bits
|
||||
inc e
|
||||
ld a, e
|
||||
cp c
|
||||
jr z, .exit
|
||||
|
||||
; shift left, carry contains whether the bit was set
|
||||
sla b
|
||||
jr c, .set
|
||||
|
||||
.clear:
|
||||
ld [hl], LED_OFF
|
||||
jr .check
|
||||
|
||||
.set:
|
||||
ld [hl], LED_ON
|
||||
jr .check
|
||||
|
||||
.exit:
|
||||
ret
|
||||
|
||||
Tick:
|
||||
; We don't want any interrupts mid-tick
|
||||
di
|
||||
|
||||
; Reset the control signals
|
||||
xor a
|
||||
ld hl, ctrl
|
||||
ld [hl+], a
|
||||
ld [hl], a
|
||||
|
||||
; Reset bus; in case we have no control signals
|
||||
ld [bus], a
|
||||
|
||||
; Operate based on current op stage
|
||||
ld a, [opc]
|
||||
ld c, a
|
||||
|
||||
; Stage 0 and 1 are the same for all operations
|
||||
cp $0
|
||||
jr z, .stage_0
|
||||
cp $1
|
||||
jr z, .stage_1
|
||||
|
||||
; Stage 2, 3, and 4 differ
|
||||
jr .stage_2_3_4
|
||||
|
||||
; Stage 0 same for all instructions: CO | MI
|
||||
.stage_0:
|
||||
ld hl, ctrl
|
||||
set CTRL_MI, [hl]
|
||||
inc hl
|
||||
set CTRL_CO, [hl]
|
||||
jr .update_leds
|
||||
|
||||
; Stage 1 same for all instructions: RO | II | CE
|
||||
.stage_1:
|
||||
ld hl, ctrl
|
||||
set CTRL_RO, [hl]
|
||||
set CTRL_II, [hl]
|
||||
inc hl
|
||||
set CTRL_CE, [hl]
|
||||
jr .update_leds
|
||||
|
||||
.stage_2_3_4:
|
||||
ld a, [ir]
|
||||
and $f0
|
||||
ld b, c
|
||||
|
||||
; NOP
|
||||
cp $00
|
||||
jr z, .update_leds
|
||||
|
||||
; LDA
|
||||
cp $10
|
||||
call z, op_lda
|
||||
|
||||
; ADD
|
||||
cp $20
|
||||
call z, op_add
|
||||
|
||||
; SUB
|
||||
cp $30
|
||||
call z, op_sub
|
||||
|
||||
; STA
|
||||
cp $40
|
||||
call z, op_sta
|
||||
|
||||
; LDI
|
||||
cp $50
|
||||
call z, op_ldi
|
||||
|
||||
; JP
|
||||
cp $60
|
||||
call z, op_jmp
|
||||
|
||||
; JC
|
||||
cp $70
|
||||
call z, op_jc
|
||||
|
||||
; JZ
|
||||
cp $80
|
||||
call z, op_jz
|
||||
|
||||
; OUT
|
||||
cp $e0
|
||||
call z, op_out
|
||||
|
||||
; HLT
|
||||
cp $f0
|
||||
call z, op_hlt
|
||||
|
||||
.update_leds:
|
||||
; These LEDs are latched by the clock so we want to display only pre-control signal evaluation
|
||||
ld a, [opc]
|
||||
ld c, 3
|
||||
ld hl, opc_led_2
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [pc]
|
||||
ld c, 4
|
||||
ld hl, pc_led_3
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [mar]
|
||||
ld c, 4
|
||||
ld hl, mar_led_3
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [ir]
|
||||
ld c, 8
|
||||
ld hl, ir_led_7
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [a_reg]
|
||||
ld c, 8
|
||||
ld hl, a_led_7
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [b_reg]
|
||||
ld c, 8
|
||||
ld hl, b_led_7
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [alu]
|
||||
ld c, 8
|
||||
ld hl, alu_led_7
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [ctrl]
|
||||
ld c, 8
|
||||
ld hl, ctrl_led_ht
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [ctrl+1]
|
||||
ld c, 8
|
||||
ld hl, ctrl_led_eo
|
||||
call UpdateLeds
|
||||
|
||||
ld a, [flags]
|
||||
ld c, 2
|
||||
ld hl, flag_led_c
|
||||
call UpdateLeds
|
||||
|
||||
; Update output display
|
||||
ld a, [out_reg]
|
||||
call CalculateBCD
|
||||
; 100s place
|
||||
ld hl, display
|
||||
ld [hl], e
|
||||
; 10s place
|
||||
inc hl
|
||||
ld [hl], c
|
||||
; 1s place
|
||||
inc hl
|
||||
ld [hl], d
|
||||
|
||||
; Update mem display
|
||||
ld a, [mar]
|
||||
ld hl, ram
|
||||
add l
|
||||
ld l, a
|
||||
ld a, [hl]
|
||||
ld [mem], a
|
||||
|
||||
; Update the control signals for next time. Order matters.
|
||||
call ctrl_ht
|
||||
call ctrl_ro
|
||||
call ctrl_io
|
||||
call ctrl_ao
|
||||
call ctrl_su
|
||||
call ctrl_fi
|
||||
call ctrl_eo
|
||||
call ctrl_co
|
||||
call ctrl_mi
|
||||
call ctrl_ri
|
||||
call ctrl_ii
|
||||
call ctrl_ai
|
||||
call ctrl_bi
|
||||
call ctrl_oi
|
||||
call ctrl_ce
|
||||
call ctrl_jp
|
||||
|
||||
; The memory LEDs are also instantaneous (they display whatever is in memory at the address in the MAR)
|
||||
ld a, [mem]
|
||||
ld c, 8
|
||||
ld hl, mem_led_7
|
||||
call UpdateLeds
|
||||
|
||||
; The bus LEDs are instantaneous (no latching), so we should always display latest
|
||||
ld a, [bus]
|
||||
ld c, 8
|
||||
ld hl, bus_led_7
|
||||
call UpdateLeds
|
||||
|
||||
; Go to next op stage
|
||||
ld a, [opc]
|
||||
inc a
|
||||
ld [opc], a
|
||||
cp 5
|
||||
jr nz, .exit
|
||||
xor a
|
||||
ld [opc], a
|
||||
|
||||
.exit:
|
||||
ei
|
||||
ret
|
Loading…
Reference in New Issue