Hi Alan, what are you using the serial port for? I've had the problem that I would miss interrupts because I was using diag_printf. This function apparently disables interrupts. Switching to printf and configuring printf such that it is interrupt driven fixed that situation for me.
To configure printf to use interrupts, I enabled CYGPKG_IO_SERIAL_DEVICES and changed CYGDAT_IO_SERIAL_TTY_CONSOLE to /dev/tty0. Hope this helps, Martin ________________________________________ From: ecos-discuss-ow...@ecos.sourceware.org [ecos-discuss-ow...@ecos.sourceware.org] on behalf of Alan Bowman [alan.michael.bow...@gmail.com] Sent: Thursday, July 19, 2012 11:46 To: ecos-discuss@ecos.sourceware.org Subject: [ECOS] Interrupt stacking issues I am using a board based upon an STM3210E development board, only with the processor clocked much slower (8MHz). I am seeing problems with interrupt handling when using the serial ports. I believe that my system should be fast enough to handle the data coming in. Recently, I started getting assertions that a stack base was corrupt. It turns out that the thread that is running when characters arrive at the serial port has many instances of the ISR stacked one on top the other until the stack overflows. I understand that the ISR uses the stack of the running thread, but I can't see how the same ISR can call enough times until the stack overflows. Since the stack check code is being asserted, I can see that the PendSV bit is being set, and the scheduler is starting the context switch - so the ISR itself is running to completion. This also seems to be quite timing dependent - when I have a setup that sees the failure, it's quite consistent as soon as a modest amount of data is written. However, inserting a few lines of debugging code into ISRs can make the issue (apparently) vanish. Has anyone else had problems with recurring ISRs like this? I'm not sufficiently clear on the inner workings of the Cortex port to be able to see if this is a problem with all interrupts, the serial ports or something that I've done. The stack dump doesn't enlighten me much (beyond showing what seems to be repetition of the ISR call and surrounding code), but I can post a printout if anyone thinks it would help. Thanks in advance Alan Bowman -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss
