【得捷电子Follow me第2期】自定义任务：esp32控制放大器

dql2016

【得捷电子Follow me第2期】自定义任务：esp32控制放大器 [复制链接]

 

在第二期的活动中为了凑单买了XIAO ESP32C3，支持arduino开发，十分方便，尺寸也十分的mini，板子带了锂电池充电芯片，可玩性非常高。

 

通过SPI接口驱动AD5270这款数字电位器，来调整仪表放大器的增益，从而实现程控增益，测试代码如下：

// AD5270 commands - new digital potentiometer
#define CMD_WR_RDAC        0x01
#define CMD_RD_RDAC        0x02
#define CMD_ST_RDAC        0x03
#define CMD_RST            0x04
#define CMD_RD_MEM         0x05
#define CMD_RD_ADDR        0x06
#define CMD_WR_CTRL        0x07
#define CMD_RD_CTRL        0x08
#define CMD_SHTDN          0x09

void vspi_write_word(const int chip_select, uint16_t data_to_send, const uint8_t bit_order, const uint8_t mode) {
  vspi->beginTransaction(SPISettings(SPI_FREQ_FAST, bit_order, mode));
  digitalWrite(chip_select, LOW);   //pull SS slow to prep other end for transfer
  vspi->transfer16(data_to_send);
  digitalWrite(chip_select, HIGH);  //pull ss high to signify end of data transfer
  vspi->endTransaction();
}

/* Write a 4-bit command and a 10-bit data word */
void AD5270_Write(const int chip_select, uint8_t cmd, uint16_t data){
  uint16_t data_word = ((cmd & 0x0F) << 10) | (data & 0x03FF);
  vspi_write_word(chip_select, data_word, MSBFIRST, SPI_MODE1);
}

/* Enable/disable rheostat value changes */
void AD5270_LockUnlock(const int chip_select, uint8_t lock){
  AD5270_Write(chip_select, CMD_WR_CTRL, lock ? 0 : 0x002);
}

/* Enable/disable hardware shutdown */
void AD5270_Shutdown(const int chip_select, uint8_t shutdown){
  AD5270_Write(chip_select, CMD_SHTDN, shutdown ? 1 : 0);
}

/* Set the value of the digital rheostat - range is 0-0x3FF (0-100kOhm) */
void AD5270_Set(const int chip_select, uint16_t val)
{
  AD5270_Write(chip_select, CMD_WR_RDAC, val);
}

#define CHIP_SEL_MEAS      10   // Chip select pin for measuring digital rheostat potentiometer

void setup() {
  // put your setup code here, to run once:
      // Set voltage measurement gain to 1 (maximum current (5V pk-pk) must be within ADC range)
    AD5270_Shutdown(CHIP_SEL_MEAS, 1);
  AD5270_Set(CHIP_SEL_MEAS, 100);

}

void loop() {
  // put your main code here, to run repeatedly:

}

 

 

开发板支持wifi功能，可以实现分布式的数据采集，非常强大。 

 

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