Hi,
Not sure what steps you have taken to enable a watchdog but from
the symptoms looks like two things could be going on:
- Feed sequence is incorrect or incomplete and triggers reset
- Time-out value is incorrect and causes watchdog to trigger either
immediately or very quickly
Generally interrupts should be disabled before feeding or programming
the watchdog, and enabled afterwards. Double check your code and make
sure that your time-out constant is correct and you disable,access
watchdog and then enable interrupts.
In any case chip is probably reseting all the time once it gets to
execute your code. This will make it look totally unresponsive but
it should be recoverable even without JTAG.
To program it you have to force it to go into ISP (boot loader)
before executing any of your code. One way to do it is to tie both
RESET and P0.14 pins LOW and then power cycle chip. Release the
RESET high and it will go directly into the ISP before executing
your code and causing problems with the watchdog.
Good luck!
elektrknight
> Hi.
>
> First, sorry for my poor english.
>
> I programmed my LPC2103 several times succesfully, but after I
enabled
> a watchdog, the chip lock and no more responded for
programming
> command, it also stop speaking via JTAG. So I replaced LPC2103 on by
> board and then I can work with it, but again when I enabled a
> watchdog, chip stop talking. Now what I can do? What to check?
What
> can be wrong with my program? I can replace another
LPC2103 but i
> don't know if it lock again?
>
> Mariusz Koniarz
>
