Nano 33 BLE: SPI Max Freq is 8 Mhz?

[mjs513]

Testing on the nano 33 (ble and sense) shows the Max SPI is 8Mhz. According to the data sheet the Max clock for SPI is suppose to be 32Mhz.

Setting the clock to 30 mhz in begin transaction:

Sketch used:

#include <SPI.h>
#define SPIX SPI
#define CS_PIN 6
void setup() {
  Serial.begin(115200);
  while (!Serial && millis() < 5000) {}
  Serial.print("\nBefore SPI.begin: type any character to start\n");
  while (!Serial.available()) {
    yield();
  }
  SPIX.begin();
  Serial.print("\nAfter SPI.begin: type any character to start\n");
  while (!Serial.available()) {
    yield();
  }
  SPIX.beginTransaction(SPISettings(30000000, MSBFIRST, SPI_MODE0));

  pinMode(CS_PIN, OUTPUT);
  digitalWrite(CS_PIN, HIGH);
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, LOW);
  Serial.print("paused setup");
  while(Serial.read() == -1){}
  while(Serial.read() != -1) {}

}

void loop() {
  digitalWrite(CS_PIN, LOW);
  digitalWrite(LED_BUILTIN, HIGH);
  for(uint8_t i = 'a'; i <='f'; i++) SPIX.transfer(i);
  digitalWrite(LED_BUILTIN, LOW);
  digitalWrite(CS_PIN, HIGH);
  delay(50);
  //Serial.print("paused");
  //while(Serial.read() == -1){}
  //while(Serial.read() != -1) {}

}

[mjs513]

I ran same sketch under Mbed and saw same Max Freq of 8mhz. Think you all need to updated the datasheet.