I have an LPC1769 used as a supervisory micro for an i.MX53 based system, there are various lines between the two cpu's, i.e I2C, USB .. lot's of GPIO lines etc.
I am having an issue with coming out of sleep. Initially with the i.MX53 not running (before it's rails come up) the LPC1769 enters and exits sleep mode fine. However,
after the i.MX53 starts running and I try to sleep the LPC, it sleeps but no longer wakes from sleep.
My question is: Is there any conditions on the IO pins that could stop the LPC from coming out of sleep? The only pin I am aware of is P1.16 which when low on reset causes the
LPC to enter bootloader mode, I have made sure that this line is pulled up to the LPC 3v3 rail. (The LPC has a separate always on 3V3 rail ..)
Thanks in advance.