Weird problem on rs232 vs USB-serial...
mike
antispam21 at verizon.net
Tue Feb 24 17:47:23 UTC 2009
Thanks Chris,
The interrupts were checked out fine. I was able to see the bootrom
messages (a very basic bootrom) when it came up. The problem
occurred only after I loaded an RTEMS app (with the RTEMS shell
and some debug codes) to ram, then jump to it that I didn't see anything.
Repeating the same sequence with the Leon2 uart connected to
a USB<->serial adapter (to the same Linux host) worked fine.
The simple RTEMS app just use /dev/console for i/o and it didn't
seems that it could have anything wrong with it as it worked as it's
supposed to **when connected to usb<->serial** without changing
anything.
That's really weird...
-mike-
Chris Johns wrote:
>
> Check /proc/interrupts to see if the kernel is getting interrupts from
> the UART for ttyS1. I would not bother with USB interrupts as this is
> a shared bus and the interrupt count to USB serial I/O does not match
> easily.
>
> I would also connect just a cable to the port and connect together the
> TX/RX pins then type something on Minicom. You should see the
> interrupt count go up by 2 for each character pressed. This will help
> you isolate the host from cable from target.
>
> Regards
> Chris
>
>
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