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HAND THAT FEEDS

It happens to the best of us. Treat the watchdog timer nicely. It bites. I wanted to protect my sensor from the possibility of the processor locking up and potentially placing DC on the pins because it would be death to this type of sensor. Not that I had a problem. I did it more to prevent any problems. I implemented the watchdog timer in the software, but the timeout was way too short. It was so short that there was no way I could program the flash memory. It appears that the watchdog timer was resetting the device before the start of the flash memory programming cycle could begin. I was locked out of the chip.

Solution: I deleted that bit of code and got busy with the soldering iron and a second LPC2138.I’m sure the watchdog timer works perfectly—in my case, too perfectly.