[参考译文] ADS1298：SPI 通信出现故障

尊敬的 Abdelrahman：

感谢您发帖。 您能否共享读取器件 ID 寄存器的 SPI 帧的逻辑分析仪捕获结果？  

此致、

Ryan

e2e.ti.com/.../ADS129X_5F00_File.zip

尊敬的 Ryan：

感谢您的 快速响应。 我已经附上了一个 ZIP 文件、其中包含代码以及来自逻辑分析仪的片段、供您参考。

在代码中、我使用 HSPI 命令、因为我要处理 ESP32上的 HSPI 引脚。 如果您能查看随附的文件并就此问题提供进一步的指导、我将不胜感激。

此致！
Abdelrahman

您好、Ryan、  

我调整了 SPI 配置、现在、当 nCS 处于低电平时、调整了 SCLK。 此外、我能够使用 MOSI 发送命令、但 MISO 上没有活动。 我上传了一个 zip 文件夹中的逻辑分析仪图像+代码。 如果您能为我提供进一步的指导、我将不胜感激。  

#include <SPI.h>

// Define the SPI pins for HSPI (on ESP32 or custom setup)
#define HSPI_MISO   12
#define HSPI_MOSI   13
#define HSPI_SCLK   14
#define HSPI_SS     15
#define PWDN_PIN    32  // Define the PWDN control pin for ADS1298

static const int spiClk = 150000; // 150 kHz clock speed

// Uninitialized pointer to SPI object
SPIClass *hspi = NULL;

void setup() {
  // Initialize serial for debugging
  Serial.begin(115200);
  
  // Initialize instance of the SPIClass attached to HSPI
  hspi = new SPIClass(HSPI);

  // Initialize SPI bus with default pins SCLK = 14, MISO = 12, MOSI = 13, SS = 15
  hspi->begin(HSPI_SCLK, HSPI_MISO, HSPI_MOSI, HSPI_SS);

  // Set SS as output and set it high to start with (deselect)
  pinMode(HSPI_SS, OUTPUT);
  digitalWrite(HSPI_SS, HIGH);

  // Set up the PWDN control pin
  pinMode(PWDN_PIN, OUTPUT);

  // Power up the ADS1298 by setting PWDN pin HIGH
  digitalWrite(PWDN_PIN, HIGH);
  delay(100);  // Small delay to ensure the device powers up

  Serial.println("ADS1298 Powered Up");
}

void loop() {
  // Optionally: Add logic to enter Power-Down mode (if needed)
  // digitalWrite(PWDN_PIN, LOW);  // Pull LOW to enter Power-Down mode
  // delay(1000);  // Delay to simulate Power-Down mode

  byte commands[] = {0x0A, 0x20, 0x00};  // Array of commands
  byte response;                         // Variable to hold the response from the slave
  byte deviceID = 0x00;                  // Device ID

  // Start SPI transaction for sending the commands
  hspi->beginTransaction(SPISettings(spiClk, MSBFIRST, SPI_MODE1));

  // Pull SS low to select the slave
  digitalWrite(HSPI_SS, LOW);
  delayMicroseconds(10);  // Small delay to stabilize the signal
  
  // Send the command bytes to the slave
  for (int i = 0; i < sizeof(commands) / sizeof(commands[0]); i++) {
    response = hspi->transfer(commands[i]);  // Send and receive at the same time
    Serial.print("Sent command: ");
    Serial.println(commands[i], HEX);
    Serial.print("Response from slave: ");
    Serial.println(response, HEX);  // Display the response (if the slave sends any data back)
  }

  // Send and receive device ID
  response = hspi->transfer(deviceID);  // Send and receive at the same time
  Serial.print("Sent device ID command: ");
  Serial.println(deviceID, HEX);
  
  Serial.print("Response from slave: ");
  Serial.println(response, HEX);  // Display the response (if the slave sends any data back)

  // Pull SS high to deselect the slave
  digitalWrite(HSPI_SS, HIGH);

  // End SPI transaction
  hspi->endTransaction();

  delay(1000); // Wait for a second before the next loop
}