Part 4: Storage

CMakeLists.txt

@@ -3,7 +3,6 @@ cmake_minimum_required(VERSION 3.5)
 set(EXTRA_COMPONENT_DIRS "src")
 set(COMPONENTS "esptool_py src")
 
-
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 
 project(game)

README.md

@@ -2,6 +2,18 @@
 
 * Get the [ESP-IDF v4.0](https://github.com/espressif/esp-idf/releases/tag/v4.0)
 	* Follow Steps 1 through 3 of the [Documentation](https://docs.espressif.com/projects/esp-idf/en/v4.0/get-started/index.html#step-1-install-prerequisites)
+* Comment out line 303 of `esp-idf/components/driver/sdspi_host.c` to enable the shared SPI bus
+
+```c
+// Initialize SPI bus
+esp_err_t ret = spi_bus_initialize((spi_host_device_t)slot, &buscfg,
+    slot_config->dma_channel);
+if (ret != ESP_OK) {
+    ESP_LOGD(TAG, "spi_bus_initialize failed with rc=0x%x", ret);
+    //return ret;
+}
+```
+
 * Modify the `export.sh` script in this directory and fill out `IDF_PATH` and `IDF_TOOLS_PATH`
 	* `IDF_PATH` is the extracted ESP-IDF
 	* `IDF_TOOLS_PATH` is the path to the toolchain

src/CMakeLists.txt

@@ -3,10 +3,12 @@ idf_component_register(
 	"main.c"
 	"odroid/display.c"
 	"odroid/input.c"
+	"odroid/sdcard.c"
 
 	INCLUDE_DIRS
 	"."
 
 	PRIV_REQUIRES
-	"esp_adc_cal")
+	"esp_adc_cal"
+	"fatfs")
 

src/main.c

@@ -1,5 +1,6 @@
 #include "odroid/display.h"
 #include "odroid/input.h"
+#include "odroid/sdcard.h"
 #include "macros.h"
 #include <esp_log.h>
 #include <freertos/FreeRTOS.h>
@@ -14,6 +15,25 @@ void app_main(void)
 {
 	Odroid_InitializeInput();
 	Odroid_InitializeDisplay();
+	Odroid_InitializeSdcard();
+
+	// Load sprite
+	uint16_t* sprite = (uint16_t*)malloc(64 * 64 * sizeof(uint16_t));
+	{
+		FILE* spriteFile = fopen("/sdcard/key", "r");
+		assert(spriteFile);
+
+		for (int i = 0; i < 64; ++i)
+		{
+			for (int j = 0; j < 64; ++j)
+			{
+				fread(sprite, sizeof(uint16_t), 64 * 64, spriteFile);
+			}
+		}
+
+		fclose(spriteFile);
+	}
+
 
 	ESP_LOGI(LOG_TAG, "Odroid initialization complete - entering main loop");
 
@@ -39,12 +59,40 @@ void app_main(void)
 		else if (input.start) { color = SWAP_ENDIAN_16(RGB565(0, 0, 0xff)); }
 		else if (input.select) { color = SWAP_ENDIAN_16(RGB565(0xff, 0xff, 0xff)); }
 
-		for (int row = y; row < y + 50; ++row)
+		int spriteRow = 0;
+		int spriteCol = 0;
+
+		for (int row = y; row < y + 64; ++row)
 		{
-			for (int col = x; col < x + 50; ++col)
+			spriteCol = 0;
+
+			for (int col = x; col < x + 64; ++col)
 			{
-				gFramebuffer[LCD_WIDTH * row + col] = color;
+				uint16_t pixelColor = sprite[64 * spriteRow + spriteCol];
+
+				if (pixelColor != 0)
+				{
+					gFramebuffer[row * LCD_WIDTH + col] = color;
+				}
+
+				++spriteCol;
 			}
+
+			++spriteRow;
+		}
+
+		if (input.menu)
+		{
+			const char* snapFilename = "/sdcard/framebuf";
+
+			ESP_LOGI(LOG_TAG, "Writing snapshot to %s", snapFilename);
+
+			FILE* snapFile = fopen(snapFilename, "wb");
+			assert(snapFile);
+
+			fwrite(gFramebuffer, 1, LCD_WIDTH * LCD_HEIGHT * sizeof(gFramebuffer[0]), snapFile);
+
+			fclose(snapFile);
 		}
 
 		Odroid_DrawFrame(gFramebuffer);

src/odroid/sdcard.c

@@ -0,0 +1,33 @@
+#include "sdcard.h"
+#include <esp_vfs_fat.h>
+#include <driver/sdmmc_host.h>
+#include <driver/sdspi_host.h>
+#include <sdmmc_cmd.h>
+
+
+static const gpio_num_t SD_PIN_MISO = GPIO_NUM_19;
+static const gpio_num_t SD_PIN_MOSI = GPIO_NUM_23;
+static const gpio_num_t SD_PIN_SCLK = GPIO_NUM_18;
+static const gpio_num_t SD_PIN_CS = GPIO_NUM_22;
+
+
+void Odroid_InitializeSdcard()
+{
+	sdmmc_host_t host = SDSPI_HOST_DEFAULT();
+	host.slot = VSPI_HOST;
+
+	sdspi_slot_config_t slot_config = SDSPI_SLOT_CONFIG_DEFAULT();
+	slot_config.gpio_miso = SD_PIN_MISO;
+	slot_config.gpio_mosi = SD_PIN_MOSI;
+	slot_config.gpio_sck = SD_PIN_SCLK;
+	slot_config.gpio_cs = SD_PIN_CS;
+
+	esp_vfs_fat_sdmmc_mount_config_t mount_config = {};
+	mount_config.format_if_mount_failed = false;
+	mount_config.max_files = 5;
+
+	sdmmc_card_t* card;
+
+	ESP_ERROR_CHECK(esp_vfs_fat_sdmmc_mount("/sdcard", &host, &slot_config, &mount_config, &card));
+}
+

src/odroid/sdcard.h

@@ -0,0 +1,5 @@
+#pragma once
+
+
+void Odroid_InitializeSdcard(void);
+