spi连续读取多个从设备进入硬件错误

发布于 2024-04-11 09:19:11 浏览：314 订阅该版

[tocm]

## 问题描述：
spi总线上挂载16个从设备，初始化时将从设备find之后将设备指针句柄放在一个数组内，读取数倍数据时轮询数组即可，但是现在问题是轮询时如果从设备数量不超过8个可以读取到数据，要想加到16个就必须在读取一个从设备后加延时函数才可以，

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20240411/a36d962345258936ec01095ba1270c29.png)

部分代码如下
```c
#include "read_temp.h"
int temp_pro[SENSOR_NUM]; 
int temp[SENSOR_NUM];
struct rt_spi_device *spi_device[SENSOR_NUM];
const Read_Temp read_temp_par[] = {//按实际情况更改此表数据
//---*spi_dev_name----spi_device----cs_pin---------------temp_pro----------temp
	{"spi10",		  		GET_PIN(C, 5),		&temp_pro[0],     &temp[0]},
	{"spi11",		   		GET_PIN(C, 5),		&temp_pro[1],     &temp[2]}
};
uint8_t read_tmnp_num = sizeof(read_temp_par)/sizeof(read_temp_par[0]);//计算表的长度,也就是传感器的个数
struct rt_spi_configuration cfg;

static void init_spi(void)
{
	cfg.data_width = 8;
	cfg.mode = RT_SPI_MASTER | RT_SPI_MODE_0 | RT_SPI_MSB;
	cfg.max_hz = 10 *1000;                           /* 10k */
}
void sensor_init(void)
{
	init_spi();
	for(uint8_t i = 0;i < read_tmnp_num;i++)
	{
		rt_pin_mode(read_temp_par[i].cs_pin, PIN_MODE_OUTPUT);
		rt_hw_spi_device_attach(SPI_NAME,read_temp_par[i].spi_dev_name,read_temp_par[i].cs_pin);
		spi_device[i] = (struct rt_spi_device *)rt_device_find(read_temp_par[i].spi_dev_name);
		if (!spi_device[i])
			rt_kprintf("spi sample run failed! can't find %s device!\n", read_temp_par[i].spi_dev_name);
		else
			rt_spi_configure(spi_device[i], &cfg);
	}
}
int spi_read(struct rt_spi_device *dev,uint8_t idex)
{
	//读取温度函数????????????
}
static void read_temp(void)
{
	for(uint8_t i = 0;i < read_tmnp_num;i++)
	{
		read_temp_par[i].temp[i] = spi_read(spi_device[i],i);
		if(read_temp_par[i].temp[i] != read_temp_par[i].temp_pro[i])
		{
			read_temp_par[i].temp_pro[i] = read_temp_par[i].temp[i];
		}
	}
}

```