Fun with SD cards

Other Hardware Storage
1

Hi,

Not a request for assistance, as I have fixed my problem.
My project, started 2 years ago, is for a CNC add-on to my bench drill.
It uses a Mega, an SD shield for automatic running (with commands from a text file), & a CNC shield.
A year ago, the auto run worked fine; no problem with the SD card.
After a lot of re-writing of various functions, I recently got around to re-doing the auto-run bit. Impossible to initialise the SD cards!
I spent yesterday searching for a solution, & at last discovered that I could not use the 64GB SD cards I bought recently, because my PC would not format them in FAT32.
I suggest putting an extra line in the SD card basic set-up example, along with "wiring OK?", "SD card inserted?", to ask if the SD card was set up with the correct format!
I see that there are other libraries (other than SD.h), but I don't need to investigate further, as my problem is fixed.

Regards,
Diksan

2

indeed next time you want to explore a bit more, have a look at sdFat and there is a formatter sketch

3

Hi JML,

Thanks for that. So far, I've had no replies telling me to RTFM!
I must have missed the bit in the SDmaster library (if it exists) that mentioned
SD card format & size limits.
I can now play around, setting up a 200-character command string to do some engraving with my kit.
Regards,
Diksan

4

:wink:

It’s a different library. The default SD library is based on a simplified old version of SdFat. So moving to this library brings you some fixes and better APIs/support for the file systems.

But as you said if it ain’t broken don’t fix it :slight_smile: