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Driver + example for MCP4725 12-bit I2C DAC

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UncleRus 2016-11-19 21:25:21 +05:00
parent 6481f71ce0
commit 16b38f94b0
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extras/mcp4725/mcp4725.c Normal file
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/*
* Driver for 12-bit DAC MCP4725
*
* Part of esp-open-rtos
* Copyright (C) 2016 Ruslan V. Uss <unclerus@gmail.com>
* BSD Licensed as described in the file LICENSE
*/
#include "mcp4725.h"
#include <i2c/i2c.h>
#define CMD_DAC 0x40
#define CMD_EEPROM 0x60
#define BIT_READY 0x80
static void read_data(uint8_t addr, uint8_t *buf, uint8_t size)
{
i2c_start();
i2c_write(addr << 1 | 1);
while (size--)
*(buf++) = i2c_read(!size);
i2c_stop();
}
bool mcp4725_eeprom_busy(uint8_t addr)
{
uint8_t res;
read_data(addr, &res, 1);
return !(res & BIT_READY);
}
mcp4725_power_mode_t mcp4725_get_power_mode(uint8_t addr, bool eeprom)
{
uint8_t buf[4];
read_data(addr, buf, eeprom ? 4 : 1);
return (eeprom ? buf[3] >> 5 : buf[0] >> 1) & 0x03;
}
void mcp4725_set_power_mode(uint8_t addr, mcp4725_power_mode_t mode, bool eeprom)
{
uint16_t value = mcp4725_get_raw_output(addr, eeprom);
uint8_t data[] = {
(eeprom ? CMD_EEPROM : CMD_DAC) | ((uint8_t)mode << 1),
value >> 4,
value << 4
};
i2c_slave_write(addr, data, 3);
}
uint16_t mcp4725_get_raw_output(uint8_t addr, bool eeprom)
{
uint8_t buf[5];
read_data(addr, buf, eeprom ? 5 : 3);
return eeprom
? ((uint16_t)(buf[3] & 0x0f) << 8) | buf[4]
: ((uint16_t)buf[0] << 4) | (buf[1] >> 4);
}
void mcp4725_set_raw_output(uint8_t addr, uint16_t value, bool eeprom)
{
uint8_t data[] = {
(eeprom ? CMD_EEPROM : CMD_DAC),
value >> 4,
value << 4
};
i2c_slave_write(addr, data, 3);
}