68HC11A1 troubleshooting

Hi, I built a small 68HC11A1 board about a year ago and recently dug it out from my junk box with intent of using it for a small robot. The problem is,
that PCBug11 (on an old 486 computer) will not talk to it. I've tested my MAX232A circuit and it's working correctly. I checked the clock pin on the HC11 and it shows a correct frequency pulse. MODA and MODB are tied to ground (bootstrap mode). Vcc is correct. My crystal is 4.9157 mhz, and the baud rate I am using is 4800. I did this a year ago and the board connected via pcbug.
On my OScope I can see pcbug sending data on the TX line, but I get no response from the microcontroller.
I remember reading somewhere that the HC11 memory can become corrupt (usually by reset bounce) preventing it from operating correctly. I used the reset chip, so I know I dont have this problem, but could something else have corrupted the memory? Is there anything else I should check before it goes in the trash? I hate to trash it because I built the board from scratch, all point to point wiring :(
The error I get is "Communication Failure".
Thanks in advance, Tom
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I'm pretty sure the HC11A1 boots at 9600 BPS not 4800 BPS.
--
- Alan Kilian <alank(at)timelogic.com>
Bioinformatics Applications Director, TimeLogic Corporation
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I'm using a 4.9152mhz crystal. You calculate the baud rate based on the crystal. 4800 is the correct baud for my crystal (I've connected successfully to this board before at 4800).
Any other ideas?
Thanks -tom
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wrote:

Try starting it "special test mode" MODB=0 MODA=1
This will reset the CONFIG EEPROM cell which may have been corrupted.
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Do I keep it in this mode while trying to connect with PCBUG, or do I only try this once and then switch back to MODA=0 MODB=0 ?
Thanks Tom
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That worked! Thanks!
-tom
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