I am developing an application which needs to transfer a file from a pi pico sd adapter to another via wireless safe link(eavesdrop safe).
I mind to use a ir transceiver kinda: https://www.amazon.co.uk/SODIAL-Infrared-Transceiver-Decoder-Communication/dp/B075LGSLPF Because it's not RF, thus dificults eavesdrop.
For error correction i am guessing to use zmodem protocol, no library?
Already tried GitHub - gdsports/XYmodem: Arduino XYMODEM file transfer protocol, which works partially, sometimes transfer fails, and i am afraid of SPI bus misbeheaviour(need pull up?). The spi bus also has a sh1106 display.