I’m running BeagleBone Black Rev C.
I have developed my own custom cape, it is using the following IO-pins:
BBB GPIO no
I have developed a device tree overlay, that’s declaring all the pins as GPIOs, and I have set all pins to output with value 0. Other than that am I using the VDD_3V3 and VDD_5V.
When I put the cape on, I get some error mesaages on dmesg:
[ 159.482950] mmcblk0: error -110 sending status command, retrying
[ 159.489379] mmcblk0: error -110 sending status command, aborting
[ 159.495725] end_request: I/O error, dev mmcblk0, sector 497760
At this point I can still type in some simple commands to the commandline (such as ls and cd) but more demanding commands fails (such as top and shutdown), it gives me an I/O error.
So it seems that the MMC-card for some reason is unreachable. The cape doesn’t seem to affect the supply voltage, is was measured on VDD_3V3 (P9_3) to be 3,15V both before and after I put the cape on.
Does anybody have any clues, or any suggestions to how I could do further debugging?