Subject:
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Re: Another assembly question
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Newsgroups:
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lugnet.robotics.handyboard
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Date:
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Tue, 14 Mar 2000 23:05:12 GMT
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Viewed:
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1445 times
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the fact that the two LEDs come on and then go off suggests that you *are*
successfully putting the hc11 into download mode.
it also happens that the hc11 TxD pin is in what's called "wired OR mode"
during bootstrap. this means that it can only drive a low/0v state and
requires a pullup resistor (resident on the HB) to generate the high state.
so i would check the resistors involved in the serial line ckt -- most
notable, resistor pack RP4. this should be a pack of four discrete 1K
resistors. if you have a pack of 7 common-bussed resistors that would be
problems.
fred
In lugnet.robotics.handyboard, Darin Greene writes:
>
>
> I'm also at the point of trying to download to my partially assembled board
> for the first time. I'm able to put the board in to download mode (both led's
> come on for a short period of time then go off). When I start downloading the
> green led on the interface blinks, but the led on the main board doesn't. I've
> watched the voltage coming out of the 232 chip and seen it vary while the
> download is happening, I've also watched the voltage on the Rx pin of the 6811
> do the same thing. The Tx pin of the 6811 is always low during the download.
> So I'm suspecting I' haven't managed to get the 6811 (an A1 I got from BG
> Micro) in to download mode. I checked that at power on the two pins to put the
> 6811 in bootstrap mode are both low as the manual suggests. Now I'm stuck
> and looking for suggestions on what else I can do to debug the problem.
>
> I've been using dl on my 166Mhz Win95 box from a dos prompt. I gather from
> the archives that dl automatically takes care of the config registers?
>
> Any advice, suggestions, etc. would be appreciated. Thanks in advnace
>
> Darin
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Message is in Reply To:
 | | Another assembly question
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| I'm also at the point of trying to download to my partially assembled board for the first time. I'm able to put the board in to download mode (both led's come on for a short period of time then go off). When I start downloading the green led on the (...) (25 years ago, 14-Mar-00, to lugnet.robotics.handyboard)
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