3.8.2 Serial Peripheral Interface (SPI) ESP32 features three SPIs (SPI, HSPI and VSPI) in slave and master modes in 1-line full-duplex and 1/2/4-line half-duplex communication modes. These SPIs also support the following general-purpose SPI features: • Four modes of SPI transfer format, which depend on the polarity (CPOL) and the phase (CPHA) of the SPI clock • Up to 80 MHz (The actual speed it can reach depends on the selected pads, PCB tracing, peripheral characteristics, etc.) • up to 64-byte FIFO All SPIs can also be connected to the external flash/SRAM and LCD. Each SPI can be served by DMA controllers.