esp-idf/examples/peripherals/spi_slave/README.md

1.4 KiB

SPI slave example

These two projects illustrate the SPI Slave driver. They're supposed to be flashed into two separate Espressif chips connected to eachother using the SPI pins defined in app_main.c. Once connected and flashed, they will use the spi master and spi slave driver to communicate with eachother. The example also includes a handshaking line to allow the master to only poll the slave when it is actually ready to parse a transaction.

The default GPIOs used in the example are the following:

Signal ESP32 ESP32-S2 ESP32-C3
Handshake GPIO2 GPIO2 GPIO3
MOSI GPIO12 GPIO12 GPIO7
MISO GPIO13 GPIO13 GPIO2
SCLK GPIO15 GPIO15 GPIO6
CS GPIO14 GPIO14 GPIO10

Please run wires between the following GPIOs between the slave and master to make the example function:

Slave Master
Handshake Handshake
MOSI MOSI
MISO MISO
SCLK SCLK
CS CS

Be aware that the example by default uses lines normally reserved for JTAG on ESP32. If this is an issue, either because of hardwired JTAG hardware or because of the need to do JTAG debugging, feel free to change the GPIO settings by editing defines in the top of main.c in the master/slave source code.