Parte 4: conducir

Modificación de la ESP-IDF

// 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;
}

Inicialización

8.3, . , fopen . make menuconfig, , 8.3.

FILE* spriteFile = fopen("/sdcard/key", "r");
assert(spriteFile);

uint16_t* sprite = (uint16_t*)malloc(64 * 64 * sizeof(uint16_t));

for (int i = 0; i < 64; ++i)
{
	for (int j = 0; j < 64; ++j)
	{
		fread(sprite, sizeof(uint16_t), 64 * 64, spriteFile);
	}
}

fclose(spriteFile);

int spriteRow = 0;
int spriteCol = 0;

for (int row = y; row < y + 64; ++row)
{
	spriteCol = 0;

	for (int col = x; col < x + 64; ++col)
	{
		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, sizeof(gFramebuffer[0]), LCD_WIDTH * LCD_HEIGHT, snapFile);
	}

	fclose(snapFile);
}

convert -depth 16 -size 320x240+0 -endian msb rgb565:FRAMEBUF snap.png

Referencias

• Esquema de odroid go
• Documentación ESP-IDF: SDMMC

Parte 5: batería

Esquema

LED de estado

Inicialización

static const adc1_channel_t BATTERY_READ_PIN = ADC1_GPIO36_CHANNEL;
static const gpio_num_t BATTERY_LED_PIN = GPIO_NUM_2;

static esp_adc_cal_characteristics_t gCharacteristics;

void Odroid_InitializeBatteryReader()
{
	// Configure LED
	{
		gpio_config_t gpioConfig = {};

		gpioConfig.mode = GPIO_MODE_OUTPUT;
		gpioConfig.pin_bit_mask = 1ULL << BATTERY_LED_PIN;

		ESP_ERROR_CHECK(gpio_config(&gpioConfig));
	}

	// Configure ADC
	{
		adc1_config_width(ADC_WIDTH_BIT_12);
    	adc1_config_channel_atten(BATTERY_READ_PIN, ADC_ATTEN_DB_11);
    	adc1_config_channel_atten(BATTERY_READ_PIN, ADC_ATTEN_DB_11);

    	esp_adc_cal_value_t type = esp_adc_cal_characterize(
    		ADC_UNIT_1, ADC_ATTEN_DB_11, ADC_WIDTH_BIT_12, 1100, &gCharacteristics);

    	assert(type == ESP_ADC_CAL_VAL_EFUSE_VREF);
    }

	ESP_LOGI(LOG_TAG, "Battery reader initialized");
}

Lectura de la batería

uint32_t Odroid_ReadBatteryLevel(void)
{
	const int SAMPLE_COUNT = 20;


	uint32_t raw = 0;

	for (int sampleIndex = 0; sampleIndex < SAMPLE_COUNT; ++sampleIndex)
	{
		raw += adc1_get_raw(BATTERY_READ_PIN);
	}

	raw /= SAMPLE_COUNT;


	uint32_t voltage = 2 * esp_adc_cal_raw_to_voltage(raw, &gCharacteristics);

	return voltage;
}

Ajuste de LED

void Odroid_EnableBatteryLight(void)
{
	gpio_set_level(BATTERY_LED_PIN, 1);
}

void Odroid_DisableBatteryLight(void)
{
	gpio_set_level(BATTERY_LED_PIN, 0);
}

Manifestación

uint32_t batteryLevel = Odroid_ReadBatteryLevel();

if (batteryLevel < 3600)
{
	Odroid_EnableBatteryLight();
}
else
{
	Odroid_DisableBatteryLight();
}

Referencias

• Esquema de odroid go
• Documentación ESP-IDF: ADC
• Características de la batería

Parte 6: sonido

Conceptos básicos de sonido digital

Grabar

Jugar

Tasa de muestreo

Profundidad de bits

Archivos wav

I2S

1. Transferimos datos de audio al controlador I2S
2. El controlador I2S envía datos de audio a DAC interno de 8 bits
3. Señal analógica de salidas DAC internas
4. La señal analógica se transmite al amplificador de sonido.

Multitarea

Inicialización

static const gpio_num_t AUDIO_AMP_SD_PIN = GPIO_NUM_25;

static QueueHandle_t gQueue;

static void PlayTask(void *arg)
{
	for(;;)
	{
		QueueData data;

		if (xQueueReceive(gQueue, &data, 10))
		{
			size_t bytesWritten;
			i2s_write(I2S_NUM_0, data.buffer, data.length, &bytesWritten, portMAX_DELAY);
			i2s_zero_dma_buffer(I2S_NUM_0);
		}

		vTaskDelay(1 / portTICK_PERIOD_MS);
	}
}

void Odroid_InitializeAudio(void)
{
	// Configure the amplifier shutdown signal
	{
		gpio_config_t gpioConfig = {};

		gpioConfig.mode = GPIO_MODE_OUTPUT;
		gpioConfig.pin_bit_mask = 1ULL << AUDIO_AMP_SD_PIN;

		ESP_ERROR_CHECK(gpio_config(&gpioConfig));

		gpio_set_level(AUDIO_AMP_SD_PIN, 1);
	}

	// Configure the I2S driver
	{
		i2s_config_t i2sConfig= {};

		i2sConfig.mode = I2S_MODE_MASTER | I2S_MODE_TX | I2S_MODE_DAC_BUILT_IN;
		i2sConfig.sample_rate = 5012;
		i2sConfig.bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT;
		i2sConfig.communication_format = I2S_COMM_FORMAT_I2S_MSB;
		i2sConfig.channel_format = I2S_CHANNEL_FMT_ONLY_LEFT;
		i2sConfig.dma_buf_count = 8;
		i2sConfig.dma_buf_len = 64;

		ESP_ERROR_CHECK(i2s_driver_install(I2S_NUM_0, &i2sConfig, 0, NULL));
		ESP_ERROR_CHECK(i2s_set_dac_mode(I2S_DAC_CHANNEL_LEFT_EN));
	}

	// Create task for playing sounds so that our main task isn't blocked
	{
		gQueue = xQueueCreate(1, sizeof(QueueData));
		assert(gQueue);

		BaseType_t result = xTaskCreatePinnedToCore(&PlayTask, "I2S Task", 1024, NULL, 5, NULL, 1);
		assert(result == pdPASS);
	}
}

• modo
  • configuramos el controlador como maestro (control del bus), un transmisor (porque transferimos datos a los destinatarios) y lo configuramos para usar el DAC incorporado de 8 bits (porque la placa Odroid Go no tiene un DAC externo).
• tasa_muestra
  • 5012, , , . , , . -, 2500 .
• bits_per_sample
  • , ESP32 8-, I2S , 16 , 8 .
• communication_format
  • , , - , 8- 16- .
• channel_format
  • GPIO, IN+ — IO26, «» I2S. , I2S , IO25, , .
• dma_buf_count dma_buf_len
  • DMA- ( ) , , , IDF. , .

Reproducir sonido

void Odroid_PlayAudio(uint16_t* buffer, size_t length)
{
	QueueData data = {};

	data.buffer = buffer;
	data.length = length;

	xQueueSendToBack(gQueue, &data, portMAX_DELAY);
}

Manifestación

// Load sound effect
uint16_t* soundBuffer;
int soundEffectLength = 1441;
{
	FILE* soundFile = fopen("/sdcard/jump", "r");
	assert(soundFile);

	uint8_t* soundEffect = malloc(soundEffectLength);
	assert(soundEffect);

	soundBuffer = malloc(soundEffectLength*2);
	assert(soundBuffer);

	fread(soundEffect, soundEffectLength, 1, soundFile);

    for (int i = 0; i < soundEffectLength; ++i)
    {
        // 16 bits required but only MSB is actually sent to the DAC
        soundBuffer[i] = (soundEffect[i] << 8u);
    }
}

int lastState = 0;

for (;;)
{
	[...]

	int thisState = input.volume;

	if ((thisState == 1) && (thisState != lastState))
	{
		Odroid_PlayAudio(soundBuffer, soundEffectLength*2);
	}

	lastState = thisState;

	[...]
}

Fuente

Referencias

• Esquema de odroid go
• Hoja de datos del amplificador de audio
• Documentación ESP-IDF: DAC
• Documentación ESP-IDF: I2S
• Formato de archivo WAVE
• Video: Explicación de la profundidad de bits
• Video: Explicación de la frecuencia de muestreo