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psas / stm32

PSAS STM32F4xx firmware development.
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GPS board doesn't start when cold #60

Open ThirteenFish opened 9 years ago

ThirteenFish commented 9 years ago

When powering up from completely off the STM32 on the GPS board won't start. When either delaying ChibiOS init by a second or two, or by connecting with gdb and doing soft resets everything is fine. Our current hypothesis that the external oscillator is taking too long to come up when cold, and ChibiOS can't deal with the external oscillator being not ready when it tries to switch to it. I would not be shocked if no one has ever tested the failure path there.

DevinLorenzen commented 9 years ago

is that the 25<Hz clock that could have been causing GPS problems?

From: Theo Hill Sent: ‎Wednesday‎, ‎June‎ ‎17‎, ‎2015 ‎2‎:‎15‎ ‎AM To: psas/stm32

When powering up from completely off the STM32 on the GPS board won't start. When either delaying ChibiOS init by a second or two, or by connecting with gdb and doing soft resets everything is fine. Our current hypothesis that the external oscillator is taking too long to come up when cold, and ChibiOS can't deal with the external oscillator being not ready when it tries to switch to it. I would not be shocked if no one has ever tested the failure path there.

— Reply to this email directly or view it on GitHub.

andrewgreenberg commented 9 years ago

Kind of? It's the 25 MHz crystal oscillator on the STM32, which gets all digitally and then send out as the 25 MHz clock to the MAX2769. So, not really related, because any problem in the 25 MHz digital output to the MAX shouldn't affect the crystal oscillator.