README

This sample transfers some data bytes (20000 bytes by default) via the SPI0 master to a SPI slave device and displays the first 128 bytes of the received bytes. You can connect GPIO9 and GPIO10 (Broadcom numbering) together. The sent data will also be received then.

The pinout of the SPI0 master is as follows:

SCLK	GPIO11
MOSI	GPIO10
MISO	GPIO9
CE0	GPIO8
CE1	GPIO7

Because the SPI transfer is done using DMA the CPU can do other things while the transfer is running. In this sample it is turning a rotor in the upper right corner of the screen. You can do something else here.

The SPI_CLOCK_SPEED is set to 10000 Hz by default so that the transfer takes some time (in fact exactly 20000*8 / 10000 = 16 seconds).

On the Raspberry Pi 2/3 you should disable the #define ARM_ALLOW_MULTI_CORE in include/circle/sysconfig.h if you do not use multiple CPU cores. This is done by default now.
