ESP32-S2 SPI pinout using IO MUX?

[paclema]

Hi,

I want to use the SPI capabilities of an ESP32-S2 (with external flash and PSRAM) to connect an RFM95W LoRa module but It is not clear to me what GPIO I must use to get the best performance.

I have seen in the datasheet that I could use whatever GPIO but if I use the SPI2 or SPI3 taking the IO MUX pins, I could reach a higher 80 MHz frequency.

For the ESP32 documentation the pinout is explained here: https://docs.espressif.com/projects/esp ... and-io-mux but for the ESP32-S2 is not https://docs.espressif.com/projects/esp ... aster.html.

Checking the page 42 (Appendix A – ESP32-S2 Pin Lists A.1. IO MUX) from the ESP32-S2 datasheet: https://www.espressif.com/sites/default ... eet_en.pdf

15 GPIO10 - FSPICS0 - FSPIIO4 - FSPICS0
16 GPIO11 - FSPID - FSPIIO5 - FSPID
17 GPIO12 - FSPICLK - FSPIIO6 - FSPICLK
18 GPIO13 - FSPIQ - FSPIIO7 - FSPIQ
19 GPIO14 - FSPIWP - FSPIDQS - FSPIWP
...
37 GPIO33 - FSPIHD - SPIIO4
38 GPIO34 - FSPICS0 - SPIIO5
39 GPIO35 - FSPID - SPIIO6
40 GPIO36 - FSPICLK - SPIIO7
41 GPIO37 - FSPIQ - SPIDQS
42 GPIO38 - FSPIWP - .

I assume from page 32 of the datasheet that the FSPI*** represents the SPI2 but I am not sure if I should better use the GPIO34-37 or GPIO10-13? What would be the best?

Thanks!