这篇介绍的时高精度、速度AD芯片AD7190的驱动，针对STM32，并且使用的时HAL库，改成其他库也很容易，只需要把相关通讯部分改了就行。

1. SPI设置，首先看AD7190的手册时序图

时序图中已经包含了很多信息，所以SPI配置如下，其中时钟最高为5M，在数据手册中看到的t3有最小时间限制：

1. CS引脚可以一直为低的状态，表示一直选中，如果要多片通讯，可以设置为其他，先把驱动程序放出来

#include "ad7190.h"//#define CS_H HAL_GPIO_WritePin(SPI1_NSS_GPIO_Port, SPI1_NSS_Pin, GPIO_PIN_SET)//#define CS_L HAL_GPIO_WritePin(SPI1_NSS_GPIO_Port, SPI1_NSS_Pin, GPIO_PIN_RESET)static AD7190_REG_T ad7190_obj;void init_AD7190_reg_cmds(AD7190_REG_Ptr ad7190_reg_ptr);unsigned char SPIDEV1_single_transfer(unsigned char data_byte){uint8_t data=0;//CS_L;//HAL_Delay(1);HAL_SPI_TransmitReceive(&hspi4, &data_byte, &data, 1, 1000);//HAL_Delay(1);//CS_H;return 0;}int SPIDEV1_transfer(unsigned char *send, unsigned char *receive, unsigned char bytes_num){//uint8_t i=0;//CS_L;//HAL_Delay(1);HAL_SPI_TransmitReceive(&hspi4, send, receive, bytes_num, 5000);//HAL_Delay(1);//CS_H;return 0;}/***************************************************************** Function Name : init_AD7190_reg_cmds* Description   : API to initialize the AD7190 commands structure*                 for communication* Returns       : None* Params        @ad7190_reg_ptr: Pointer to commands structure****************************************************************/void init_AD7190_reg_cmds(AD7190_REG_Ptr ad7190_reg_ptr){ad7190_reg_ptr->cmd_rd_ID_reg = COM_READ_ID_REG_CMD;ad7190_reg_ptr->cmd_rd_config_reg = COM_READ_CONFIG_REG_CMD;ad7190_reg_ptr->cmd_rd_data_reg = COM_READ_DATA_REG_CMD;ad7190_reg_ptr->cmd_rd_full_scale_reg = COM_READ_FULL_SCALE_REG_CMD;ad7190_reg_ptr->cmd_rd_gpocon_reg = COM_READ_GPCON_REG_CMD;ad7190_reg_ptr->cmd_rd_mode_reg = COM_READ_MODE_REG_CMD;ad7190_reg_ptr->cmd_rd_offset_reg = COM_READ_OFFSET_REG_CMD;ad7190_reg_ptr->cmd_rd_status_reg = COM_READ_STATUS_REG_CMD;ad7190_reg_ptr->cmd_wr_gpocon_reg = COM_WRITE_GPCON_RED_CMD;ad7190_reg_ptr->cmd_wr_config_reg = COM_WRITE_CONFIG_REG_CMD;ad7190_reg_ptr->cmd_wr_mode_reg = COM_WRITE_MODE_REG_CMD;}/***************************************************************** Function Name : init_AD7190_cmds* Description   : Initialize the AD7190 commands structure*                 for communication* Returns       : None* Params        : None****************************************************************/void init_AD7190_cmds(){init_AD7190_reg_cmds(&ad7190_obj);}/***************************************************************** Function Name : AD7190_configure* Description   : Configure/Write to the configuration register*                 for communication* Returns       : (-1) typecast for error, 0 for success* Params        @cbyte_2: Data to write to Most Significant Byte*               @cbyte_1: Data to write to Middle Byte*               @cbyte_0: Data to write to Least Significant Byte****************************************************************/char AD7190_configure(unsigned char cbyte_2, unsigned char cbyte_1, unsigned char cbyte_0){char check_ret = 0x00;unsigned char ad7190_id = 0x00;ad7190_id = AD7190_get_ID();//printf("Initializing AD7190 ADC    Device ID    = 0x%x\r\n", ad7190_id);/* Go to write to configuration register */check_ret = SPIDEV1_single_transfer(ad7190_obj.cmd_wr_config_reg);/* Write to Most Significant Byte */check_ret = SPIDEV1_single_transfer(cbyte_2);/* Write to Mid Byte */check_ret = SPIDEV1_single_transfer(cbyte_1);/* Write to Least Significant Byte */check_ret = SPIDEV1_single_transfer(cbyte_0);return (check_ret);}/***************************************************************** Function Name : AD7190_mode* Description   : Configure/Write to the mode register*                 for communication* Returns       : (-1) typecast for error, 0 for success* Params        @mbyte_2: Data to write to Most Significant Byte*               @mbyte_1: Data to write to Middle Byte*               @mbyte_fs: Data to write to Least Significant Byte****************************************************************/char AD7190_mode(unsigned char mbyte_2, unsigned char mbyte_1, unsigned char mbyte_fs){char check_ret = 0x00;/* Go to write to configuration register */check_ret = SPIDEV1_single_transfer(ad7190_obj.cmd_wr_mode_reg);/* Write to Most Significant Byte */check_ret = SPIDEV1_single_transfer(mbyte_2);/* Write to Mid Byte */check_ret = SPIDEV1_single_transfer(mbyte_1);/* Write to Least Significant Byte */check_ret = SPIDEV1_single_transfer(mbyte_fs);//add new gpocon 打开switchcheck_ret = SPIDEV1_single_transfer(ad7190_obj.cmd_wr_gpocon_reg);check_ret = SPIDEV1_single_transfer(0x40);return (check_ret);}/***************************************************************** Function Name : AD7190_read_status_reg* Description   : Read the status register* Returns       : Contents of the status register* Params        : None****************************************************************/unsigned char AD7190_read_status_reg(){unsigned char status_reg = 0x00;SPIDEV1_single_transfer(ad7190_obj.cmd_rd_status_reg);status_reg = SPIDEV1_single_transfer(0x00);return (status_reg);}/***************************************************************** Function Name : AD7190_get_ID* Description   : Read the ID register* Returns       : Contents of the ID register* Params        : None****************************************************************/unsigned char AD7190_get_ID(){unsigned char ad7190_ID = 0x00;SPIDEV1_single_transfer(ad7190_obj.cmd_rd_gpocon_reg);ad7190_ID = SPIDEV1_single_transfer(0x00);return (ad7190_ID);}/***************************************************************** Function Name : AD7190_reset* Description   : Resets the AD7190* Returns       : None* Params        : None****************************************************************/void AD7190_reset(){char cnt;for(cnt = 0 ; cnt < 55; cnt++)SPIDEV1_single_transfer(0xFF);}/***************************************************************** Function Name : AD7190_read_data* Description   : Read the data register* Returns       : Contents of the data register* Params        : None****************************************************************/int AD7190_read_data(void){unsigned char Tx_bytes[]={0xff,0xff,0xff}, Rx_bytes[3] = {0,0,0}, reg_status = 0, drdy_bit;int adc_data = 0x00;//memset(Tx_bytes, 0xFF, sizeof(Tx_bytes));//memset(Rx_bytes, 0, sizeof(Rx_bytes));drdy_bit = 1;reg_status = AD7190_read_status_reg();drdy_bit = reg_status & 0x80;if (drdy_bit == 0x00){SPIDEV1_single_transfer(ad7190_obj.cmd_rd_data_reg);if (SPIDEV1_transfer(Tx_bytes, Rx_bytes, 3) == 0){adc_data = (adc_data | Rx_bytes[0]) << 8;adc_data = (adc_data | Rx_bytes[1]) << 8;adc_data = adc_data | Rx_bytes[2];//printf("%lu\r\n",adc_data);}else{//printf("(AD7190_read_test)Transaction Failed\r\n");adc_data = 0xffffffff;}}else{adc_data = 0xffffffff;}return (adc_data);}/***************************************************************** Function Name : AD7190_dump_regs* Description   : Dump the contents of the registers* Returns       : None* Params        @regs_to_dump: Registers to dump****************************************************************/void AD7190_dump_regs(REG_DumpT regs_to_dump){unsigned char Tx_bytes[3]={0xff,0xff,0xff}, Rx_bytes[3] = {0,0,0}, reg_status_id = 0;unsigned long read_config_mode = 0x00;//memset(Tx_bytes, 0xFF, sizeof(Tx_bytes));//memset(Rx_bytes, 0, sizeof(Rx_bytes));switch(regs_to_dump){case DUMP_CONFIG_REG_CONTENTS:SPIDEV1_single_transfer(ad7190_obj.cmd_rd_config_reg);if (SPIDEV1_transfer(Tx_bytes, Rx_bytes, 3) == 0){read_config_mode = (read_config_mode | Rx_bytes[0]) << 8;read_config_mode = (read_config_mode | Rx_bytes[1]) << 8;read_config_mode = read_config_mode | Rx_bytes[2];//printf("Dump - Configuration Register  = 0X%x\r\n",read_config_mode);}else{//printf("(AD7190_dump_regs)Transaction Failed\r\n");}break;case DUMP_MODE_REG_CONTENTS:SPIDEV1_single_transfer(ad7190_obj.cmd_rd_mode_reg);if (SPIDEV1_transfer(Tx_bytes, Rx_bytes, 3) == 0){read_config_mode = (read_config_mode | Rx_bytes[0]) << 8;read_config_mode = (read_config_mode | Rx_bytes[1]) << 8;read_config_mode = read_config_mode | Rx_bytes[2];//printf("Dump - Mode Register  = 0X%x\r\n",read_config_mode);}else{//printf("(AD7190_dump_regs)Transaction Failed\r\n");}break;case DUMP_STATUS_REG_CONTENTS:reg_status_id = AD7190_read_status_reg();//printf("Dump - Status Register  = 0X%x\r\n",reg_status_id);break;case DUMP_ID_REG_CONTENTS:reg_status_id = AD7190_get_ID();//printf("Dump - ID Register  = 0X%x\r\n",reg_status_id);break;case DUMP_CONFIG_AND_MODE_REG_CONTENTS:default://SPIDEV1_single_transfer(ad7190_obj.cmd_rd_config_reg);//if (SPIDEV1_transfer(Tx_bytes, Rx_bytes, 3) == 0)//{//      read_config_mode = (read_config_mode | Rx_bytes[0]) << 8;//      read_config_mode = (read_config_mode | Rx_bytes[1]) << 8;//      read_config_mode = read_config_mode | Rx_bytes[2];//      //printf("Dump - Configuration Register  = 0X%x\r\n",read_config_mode);//}//else//{//      //printf("(AD7190_dump_regs)Transaction Failed\r\n");//}//memset(Rx_bytes, 0, sizeof(Rx_bytes));//read_config_mode = 0x00;SPIDEV1_single_transfer(ad7190_obj.cmd_rd_mode_reg);if (SPIDEV1_transfer(Tx_bytes, Rx_bytes, 3) == 0){read_config_mode = (read_config_mode | Rx_bytes[0]) << 8;read_config_mode = (read_config_mode | Rx_bytes[1]) << 8;read_config_mode = read_config_mode | Rx_bytes[2];//printf("Dump - Mode Register  = 0X%x\r\n",read_config_mode);}else{//printf("(AD7190_dump_regs)Transaction Failed\r\n");}break;}}

下面时ad7190.h文件

#include "stm32h7xx_hal.h"#include "main.h"#ifndef AD7190_H_#define AD7190_H_/* Commands to write to specific registers */#define COM_WRITE_CONFIG_REG_CMD                  0x10#define COM_WRITE_MODE_REG_CMD                    0x08#define COM_WRITE_GPCON_RED_CMD                   0x28/* Commands to read from specific registers */#define COM_READ_CONFIG_REG_CMD                   0x50#define COM_READ_STATUS_REG_CMD                   0x40#define COM_READ_MODE_REG_CMD                     0x48#define COM_READ_DATA_REG_CMD                     0x58#define COM_READ_GPCON_REG_CMD                    0x68#define COM_READ_ID_REG_CMD                       0x60#define COM_READ_OFFSET_REG_CMD                   0x70#define COM_READ_FULL_SCALE_REG_CMD               0x78/* Sampling Rates */#define FS_60_HZ                                 0x50#define FS_300_HZ                                 0x10#define FS_960_HZ                                 0x05#define FS_2400_HZ                                0x02#define FS_4800_HZ                                0x01/* Register settings commands for Configuration Register */#define CONFIG_REG_CMD_MSB                        0x00#define CONFIG_REG_CMD_MID                        0x01/*May have to change Gain depending on input signal voltageSee Table 19 in AD7190 datasheet for more information*/#define CONFIG_REG_CMD_LSB                        0x01//0x1F/* Register settings commands for Mode Register */#define MODE_REG_CMD_MSB                          0x08#define MODE_REG_CMD_MID                          0x00#define MODE_REG_CMD_LSB                          FS_4800_HZ/* Read the data register continously and place the data on DOUT *///#define COMM_REG_CREAD                            0x5C/* Structure Map of AD7190 internal registers* for read and write operations*/typedef struct{unsigned char cmd_rd_status_reg;unsigned char cmd_wr_mode_reg;unsigned char cmd_rd_mode_reg;unsigned char cmd_wr_config_reg;unsigned char cmd_rd_config_reg;unsigned char cmd_rd_data_reg;unsigned char cmd_rd_ID_reg;unsigned char cmd_rd_gpocon_reg;unsigned char cmd_wr_gpocon_reg;unsigned char cmd_rd_offset_reg;unsigned char cmd_rd_full_scale_reg;}AD7190_REG_T, *AD7190_REG_Ptr;/* Enum commands to dump register contents */typedef enum{DUMP_CONFIG_REG_CONTENTS,DUMP_MODE_REG_CONTENTS,DUMP_STATUS_REG_CONTENTS,DUMP_ID_REG_CONTENTS,DUMP_CONFIG_AND_MODE_REG_CONTENTS}REG_DumpT;/* AD7190 API's */void init_AD7190_reg_cmds(AD7190_REG_Ptr ad7190_reg_ptr);void init_AD7190_cmds(void);char AD7190_configure(unsigned char cbyte_2, unsigned char cbyte_1, unsigned char cbyte_0);char AD7190_mode(unsigned char mbyte_2, unsigned char mbyte_1, unsigned char mbyte_fs);unsigned char AD7190_read_status_reg(void);unsigned char AD7190_get_ID(void);void AD7190_reset(void);int AD7190_read_data(void);void AD7190_dump_regs(REG_DumpT regs_to_dump);#endif /* AD7190_H_ */

最后初始化

init_AD7190_cmds();AD7190_reset();HAL_Delay(20);AD7190_configure(CONFIG_REG_CMD_MSB, CONFIG_REG_CMD_MID, CONFIG_REG_CMD_LSB);AD7190_mode(MODE_REG_CMD_MSB, MODE_REG_CMD_MID, MODE_REG_CMD_LSB);

1. 程序最后解读关键部分

首先芯片的读写是都要先发送要操作的寄存器，然后才是读或者写，这个程序参照了github上面的，做了改进，在AD7190_mode中打开了基准电压AGND的开关，

//add new gpocon 打开switch

check_ret = SPIDEV1_single_transfer(ad7190_obj.cmd_wr_gpocon_reg);

check_ret = SPIDEV1_single_transfer(0x40);

内部原理图如下，必须要打开开关才能正常使用

其他的在注释中已经有详细的说明，具体还可以参照数据手册