SPI communication with Ardunio nano and Arduino nano 33 ble

[heli00]

Hello everyone!

I'm currently working on a project that involves using an Arduino Nano 33 BLE, but I'm facing some challenges with SPI communication. I've tried the code below to establish a simple SPI communication between an Arduino Nano (master) and Arduino Nano 33 BLE (slave), but it does not work.

Initially, I suspected that the issue might be due to different SPI frequencies. However, even after specifying the same frequency, I'm still encountering problems. Another consideration is that the Arduino Nano 33 BLE runs on a different board and utilizes mbed OS. Could this be affecting the SPI library?

I would appreciate any guidance or assistance you could provide or have suggestions on how to troubleshoot this? Thank you in advance for your help!

Master:

#include <SPI.h>

const int SS_PIN = 10;  

void setup() {
  Serial.begin(115200);
  SPI.begin();
  SPI.beginTransaction(SPISettings(8000000, MSBFIRST, SPI_MODE0));
  pinMode(SS_PIN, OUTPUT);
  digitalWrite(SS_PIN, HIGH);  
  

}

void loop() {
  // Select the slave
  digitalWrite(SS_PIN, LOW);

  // Send address byte
  char add = 'h';  // 
  SPI.transfer(add);

  // Send data
  char data = 'A';  
  SPI.transfer(data);
  Serial.print("Sent: ");
  Serial.println(data);
  Serial.println(add);

  // Deselect the slave
  digitalWrite(SS_PIN, HIGH);

  delay(1000);
}

Slave code:

#include <SPI.h>

const int SS_PIN = 10;  

void setup() {
  Serial.begin(115200);
  pinMode(SS_PIN, INPUT);
  SPI.beginTransaction(SPISettings(8000000, MSBFIRST, SPI_MODE0));
}

void loop() {
  if(SS_PIN == LOW){  

  // Receive address byte
  char receivedAddress = SPI.transfer(' ');  
  Serial.print("Received Address: ");
  Serial.println(receivedAddress);

  // Receive data
  char receivedData = SPI.transfer(' '); 
  Serial.print("Received Data: ");
  Serial.println(receivedData);

  digitalWrite(SS_PIN, HIGH);  
  delay(1000);
  }
}