/* * Example of using MCP4725 DAC * * Part of esp-open-rtos * Copyright (C) 2016 Ruslan V. Uss * BSD Licensed as described in the file LICENSE */ #include #include #include #include #include #include #include #define I2C_BUS 0 #define SCL_PIN 5 #define SDA_PIN 4 #define ADDR MCP4725A0_ADDR0 #define VDD 3.3 inline static void wait_for_eeprom(i2c_dev_t* dev) { while (mcp4725_eeprom_busy(dev)) { printf("...DAC is busy, waiting...\n"); vTaskDelay(1); } } void user_init(void) { uart_set_baud(0, 115200); printf("SDK version:%s\n", sdk_system_get_sdk_version()); i2c_init(I2C_BUS, SCL_PIN, SDA_PIN, I2C_FREQ_100K); i2c_dev_t dev = { .addr = ADDR, .bus = I2C_BUS, }; // setup EEPROM values if (mcp4725_get_power_mode(&dev, true) != MCP4725_PM_NORMAL) { printf("DAC was sleeping... Wake up Neo!\n"); mcp4725_set_power_mode(&dev, MCP4725_PM_NORMAL, true); wait_for_eeprom(&dev); } printf("Set default DAC ouptut value to MAX...\n"); mcp4725_set_raw_output(&dev, MCP4725_MAX_VALUE, true); wait_for_eeprom(&dev); printf("And now default DAC output value is 0x%03x\n", mcp4725_get_raw_output(&dev, true)); printf("Now let's generate the sawtooth wave in slow manner\n"); float vout = 0; while (true) { vout += 0.1; if (vout > VDD) vout = 0; printf("Vout: %.02f\n", vout); mcp4725_set_voltage(&dev, VDD, vout, false); // It will be very low freq wave vTaskDelay(100 / portTICK_PERIOD_MS); } }