@TS-Russell Thanks for the quick response but this does not give me what I need.
The SPX-18018 is a Spark X product and there needed to be a manual modification to the boards.txt to reconfigure the pins to make the SD Card interface to work.
I did search for SPX-18018 with no results.
Is there a way to access the OLD FORUM POSTS where the solution was posted?
Searching IS searching the old forum posts…they should all be migrated /accessible here
The sparkx version is almost identical to the red version…searching spx 18018 yielded nothing, meaning it was very likely the posts for the red version or maybe the github that you’re remembering? 2 of the 3 open issues there are SD related and have some notes within Issues · sparkfunX/SparkFun_ESP32_Thing_Plus_C · GitHub
I remember seeing issues on the original SparkX Thing Plus C with some SD cards. Adding the 100K pull-up resistor to SD SDO (SPI POCI) solved those. I don’t remember having to change boards.txt or the variant pins_arduino.h, but it has been a while.
Thanks for the info about the pull-up resistor. I think I remember something like this but it has been several years and my memory is not the greatest.