In my application on boot the SD card is initialised and data read from it. If the ESP32 has been powered down for 10 minutes or so the SD is initialised and read correctly. If the boot is after a shorter time the SD is not recognised.
Anyone seen this before?
Yes I have seen this issue before. The cause there was that flushing/closing the SD-Card-file depended on a timing-constant of 15 minutes.
Only after 15 minutes the function sd.close() was executed. Without executing sd.close() it can happen that data is not written to the card.
In another case switching the CS-line for ILI9341 / SD-card was not done properly
This list could be expanded to hundreds of different cases.
But this says nothing about what is causing your problem.
The straight-forward way to solve your problem is not guessing around what it might be
Solving your problems is presenting the detail-facts of your case.
You should read this tutorial how you do this most effective
best regards Stefan
Hi Stefan
I’m grateful for your reply, and I’m kicking myself for not having had the sense to close the file after finishing the read. Fairly standard practice.
Many thanks for your help
It would seem I described my problem more than adequately.
Best wishes
John