These two projects illustrate the SPI Slave driver. They're supposed to be flashed into two separate ESP32s 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.
Be aware that the example by default uses lines normally reserved for JTAG. 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.
