On 6/21/2020 4:36 PM, Gregory Nutt wrote:
I will consider this possibilities, thanks.
What is driving me crazy is that it actually seems to be triggered by
the binary being bigger than 256KB (MCU has 512KB, dual bank). I
already had to use openocd from git since it would not flash the
image in that case. Now openocd flashes correctly. However, the bad
reset behavior also seems to happen in this case. I have the same
problem with optimization turned on but which increases binary size
above 256KB.
I cannot think something in the code that would change in this case,
since banks are contiguous. Maybe some chip errata, I don't know.
Yes, I do recall some issue with the F429's in this regard. There was
an errata. I believe that there are some pins in the upper 256Kb bank
that interfered with some other peripheral. DavidS would know better
than I. I thought it effected USB?
You never mention which part you are using (or perhaps wan't paying
attention). You should check the errata.
I think this is the errata I was thinking of. In the STM32F42xx and
STM32F43xx Errata sheet:
2.2.10 PA12 GPIO limitations
Description
When PA12 is used as GPIO or alternate function in input or output
mode, the data read
from Flash memory can be corrupted. This behavior is observed only
when the following
conditions are met:
• The device operates from a 2.7 to 3.6 V VDD power supply whatever
the temperature
range
• Flash memory Bank2 is used or the dual bank feature is enabled.
Impacted products
• STM32F42xxI and STM32F43xxI part numbers
• STM32F42xxG and STM32F43xxG part numbers only when dual bank
feature is
enabled.
Not impacted products
• STM32F42xxG and STM32F43xxG part numbers when dual bank feature is
disabled
• STM32F42xxE and STM32F43xxE part numbers.
Workaround
PA12 must be left unconnected on the PCB (configured as push-pull
and held Low). You
can use all the other GPIOs and all alternate functions except for
the ones mapped on
PA12. Use the OTG_HS peripheral in full-speed mode instead of the
OTG_FS peripheral.
This limitation is fixed in silicon starting from revision 3.
Note that this has been fixed in current versions.
