Add support ExFAT filesystem and check work on my SD card
Samsung EVO Plus 128Gb HD XL
All worked, support ExFat need additional 4kB flash and can`t be suppoted on NanoVNA-H (if add card slot in it)
But on H4 stiil more flash space (only ~89kB + 64kB for calibration save used from 256kB)
On Samsung EVO Plus 128Gb HD XL read speed ~300kB/sec write ~190kB/s
