spi Frequency

Set the Serial Peripheral Interface (SPI) clock frequency.


The micro:bit sets the rate of data transfer and control timing for a SPI connection. This data rate and timing signal is controlled by the SCK pin. The signal on this pin is clocked using the frequency set for it.

Simulator: This function needs real hardware to work with. It’s not supported in the simulator.

The default clock frequency is 1 Mhz (10000000 Hz). You can set the frequency for the SPI connection to some other value if you need a different data rate.


  • frequency: a number to set as the frequency for SPI bus clock. This value is the number of clock changes per second (Hz).


Read the value of the WHOAMI register from the device connected to the SPI bus. The chip select line is connected to pin 0 and the SPI signals use pins P13, P14, and P15.

pins.digitalWritePin(DigitalPin.P0, 1);
pins.spiPins(DigitalPin.P15, DigitalPin.P14, DigitalPin.P13);
pins.spiFormat(8, 3);
pins.digitalWritePin(DigitalPin.P0, 0);
let command = pins.spiWrite(143);
let whoami = pins.spiWrite(0);
pins.digitalWritePin(DigitalPin.P0, 1);
serial.writeLine("WHOAMI register value: " + whoami)

See also

spi write, spi pins, spi format

SPI Programming