124 lines
3.5 KiB
C
124 lines
3.5 KiB
C
#include <stdio.h>
|
|
#include <stdint.h>
|
|
|
|
#include "driver/gpio.h"
|
|
#include "driver/i2c.h"
|
|
#include "esp_err.h"
|
|
#include "esp_log.h"
|
|
#include "freertos/portmacro.h"
|
|
#include "hal/i2c_types.h"
|
|
|
|
/* DAC Peripheral Config */
|
|
#define DAC_SCL_PIN 12
|
|
#define DAC_SDA_PIN 13
|
|
#define DAC_LDAC_PIN 14
|
|
|
|
#define DAC_ADDR 0x64 /* I2C Address of DAC */
|
|
#define DAC_VREF 0x00 /* Use Vdd as reference voltage */
|
|
#define DAC_PD 0x00 /* Full power mode */
|
|
#define DAC_GAIN 0x00 /* Since we use external Vref, this doesn't matter */
|
|
|
|
#define ACK_EN 0x1 /* Enable i2c acknowledgment check */
|
|
#define ACK_DIS 0x0 /* Disable i2c acknowledgment check */
|
|
#define ACK_VAL 0x0 /* i2c acknowledgment value */
|
|
#define NACK_VAL 0x1 /* i2c negative-acknowledgment value */
|
|
|
|
static const i2c_port_t I2C_MASTER_PORT = 0;
|
|
|
|
static const char *TAG = "EERG";
|
|
|
|
|
|
/* Initialize and configure I2C DAC */
|
|
static void dac_init(void)
|
|
{
|
|
ESP_LOGI(TAG, "Initializing DAC I2C connection");
|
|
|
|
/* Configure µC as I2C master */
|
|
i2c_config_t i2c_conf = {
|
|
.mode = I2C_MODE_MASTER,
|
|
.scl_io_num = DAC_SCL_PIN,
|
|
.sda_io_num = DAC_SDA_PIN,
|
|
.master.clk_speed = 400000 /* 400kHz for i2c fast mode */
|
|
|
|
};
|
|
i2c_param_config(I2C_MASTER_PORT, &i2c_conf);
|
|
|
|
/* Install i2c driver */
|
|
ESP_ERROR_CHECK(i2c_driver_install(I2C_MASTER_PORT, i2c_conf.mode, 0, 0, 0));
|
|
|
|
/* Setup LDAC pin with GPIO. Tied low */
|
|
gpio_reset_pin(DAC_LDAC_PIN);
|
|
gpio_set_direction(DAC_LDAC_PIN, GPIO_MODE_OUTPUT);
|
|
gpio_set_level(DAC_LDAC_PIN, 0);
|
|
}
|
|
|
|
/* Tests for acknowledgment of i2c DAC. Return ESP_OK if so */
|
|
static esp_err_t dac_ack_test(void)
|
|
{
|
|
ESP_LOGI(TAG, "Testing I2C DAC");
|
|
/* Create i2c command handle */
|
|
i2c_cmd_handle_t cmd = i2c_cmd_link_create();
|
|
i2c_master_start(cmd);
|
|
i2c_master_write_byte(cmd, (DAC_ADDR << 1) | I2C_MASTER_READ, ACK_EN); /* R/W byte is LSB of DAC address */
|
|
i2c_master_stop(cmd);
|
|
esp_err_t ret = i2c_master_cmd_begin(I2C_MASTER_PORT, cmd, 1000 / portTICK_PERIOD_MS);
|
|
i2c_cmd_link_delete(cmd);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static esp_err_t dac_out_test(void)
|
|
{
|
|
esp_err_t ret;
|
|
uint16_t test_value = 0; /* The value sent to DAC input registers */
|
|
i2c_cmd_handle_t cmd;
|
|
|
|
for (uint16_t i = 0; i < 4096; i++){
|
|
|
|
test_value = i;
|
|
|
|
cmd = i2c_cmd_link_create();
|
|
i2c_master_start(cmd);
|
|
i2c_master_write_byte(cmd, (DAC_ADDR << 1) | I2C_MASTER_WRITE, ACK_EN); /* R/W byte is LSB of DAC address */
|
|
i2c_master_write_byte(cmd, 0x50, ACK_EN); /* Multi-write to all channels */
|
|
|
|
/* For each channel [A-D] write 2 bytes to input register */
|
|
/* V_ref + PD1 + PD0 + Gx + D11-D8 | D7-D0 */
|
|
for (uint8_t i = 0; i < 4; i++) {
|
|
uint8_t bytes[2];
|
|
bytes[0] = ((uint8_t) DAC_VREF << 7) | ((uint8_t) DAC_PD << 5) | ((uint8_t) DAC_GAIN << 4) | (test_value >> 8);
|
|
bytes[1] = test_value;
|
|
i2c_master_write_byte(cmd, bytes[0], ACK_EN);
|
|
i2c_master_write_byte(cmd, bytes[1], ACK_EN);
|
|
}
|
|
|
|
i2c_master_stop(cmd);
|
|
|
|
/* Issue the multi-write command */
|
|
/* TODO need to create array of returns and check them for error */
|
|
ret = i2c_master_cmd_begin(I2C_MASTER_PORT, cmd, 1000 / portTICK_PERIOD_MS);
|
|
i2c_cmd_link_delete(cmd);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/* Main application entrance */
|
|
void app_main(void)
|
|
{
|
|
/* Initialize and configure I2C DAC */
|
|
dac_init();
|
|
|
|
/* Test DAC */
|
|
esp_err_t ret = dac_ack_test();
|
|
if (ret != ESP_OK){
|
|
ESP_LOGE(TAG, "Failed to initialize DAC");
|
|
} else {
|
|
ESP_LOGI(TAG, "Sucessfully initialized DAC");
|
|
}
|
|
|
|
/* Loop to test DAC output */
|
|
while (1) {
|
|
dac_out_test();
|
|
}
|
|
}
|