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BF527 OTP power question

Question asked by L3Sarasota on Jan 6, 2016
Latest reply on Jan 8, 2016 by gvasanth

By mistake, I have connected the BF527 VPPOTP and VDDOTP pins to ground on my board.  I just found (from the data sheet fine print) that these pins should have been connected to 2.5V even though I didn't intend to use OTP.  The processor seems to be operating okay using the emulator and I am able to read and write to the SPI flash okay but when I try to boot using the external SPI flash it doesn't even try to access the device (no SPI clocks or activity on the SEL1 CS line).  Can someone please confirm that this mistake is probably related to not being able to do a SPI boot please?  Obviously, this is going to be very difficult if not impossible (BGA) to undo the grounds on the board and another spin will be in order (for other reasons as well) so I want to know if I'm on the right track with this issue before the next board spin.  My guess is that the processor needs to read something in the OTP in order to boot from the SPI flash.  And last, assuming this is the problem, is there any possible way to have a workaround for this just for this prototyping phase? 

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