Teensy LC max SPI Speed

[Trommik]

Hey,
I played a little bit with the Teensy LC SPI and discovered that I can't get more than 12MHz at the SCK pin. Is this the maximum setting for the Teensy LC or am I doing something wrong?
Her is my test code:

#include <SPI.h>

void setup() {
  SPI.begin();
}

void loop() {
  SPI.beginTransaction(SPISettings(24000000, MSBFIRST, SPI_MODE0)); // This outputs only a 12MHz Clock on the SCK pin
  SPI.transfer(255);
  SPI.endTransaction();
  delay(10);
}

 

[PaulStoffregen]

On LC, the max SPI clock is 12 MHz.

 

[KurtE]

I could be wrong, but my quick check is that the SPI speed has a max of F_BUS/2 on the Teensy LC and at MAX CPU of 48mhz, F_BUS set to 24mhz and so half 24/2 = 12mhz

Kurt

 

[Trommik]

Ah ok I thought F_BUS would be 48MHz.
Thanks for the correction.