66 lines
1.5 KiB
C
66 lines
1.5 KiB
C
/*
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* Example of using MCP4725 DAC
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*
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* Part of esp-open-rtos
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* Copyright (C) 2016 Ruslan V. Uss <unclerus@gmail.com>
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* BSD Licensed as described in the file LICENSE
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*/
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#include <esp/uart.h>
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#include <espressif/esp_common.h>
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#include <i2c/i2c.h>
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#include <mcp4725/mcp4725.h>
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#include <stdio.h>
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#include <FreeRTOS.h>
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#include <task.h>
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#define SCL_PIN 5
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#define SDA_PIN 4
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#define ADDR MCP4725A0_ADDR0
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#define VDD 3.3
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inline static void wait_for_eeprom()
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{
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while (mcp4725_eeprom_busy(ADDR))
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{
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printf("...DAC is busy, waiting...\n");
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vTaskDelay(1);
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}
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}
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void user_init(void)
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{
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uart_set_baud(0, 115200);
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printf("SDK version:%s\n", sdk_system_get_sdk_version());
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i2c_init(SCL_PIN, SDA_PIN);
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// setup EEPROM values
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if (mcp4725_get_power_mode(ADDR, true) != MCP4725_PM_NORMAL)
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{
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printf("DAC was sleeping... Wake up Neo!\n");
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mcp4725_set_power_mode(ADDR, MCP4725_PM_NORMAL, true);
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wait_for_eeprom();
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}
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printf("Set default DAC ouptut value to MAX...\n");
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mcp4725_set_raw_output(ADDR, MCP4725_MAX_VALUE, true);
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wait_for_eeprom();
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printf("And now default DAC output value is 0x%03x\n", mcp4725_get_raw_output(ADDR, true));
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printf("Now let's generate the sawtooth wave in slow manner\n");
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float vout = 0;
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while (true)
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{
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vout += 0.1;
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if (vout > VDD) vout = 0;
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printf("Vout: %.02f\n", vout);
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mcp4725_set_voltage(ADDR, VDD, vout, false);
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// It will be very low freq wave
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vTaskDelay(100 / portTICK_PERIOD_MS);
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}
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}
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