Subject:
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Re: Readings
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Newsgroups:
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lugnet.robotics.handyboard
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Date:
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Sun, 17 Jan 1999 23:48:19 GMT
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Original-From:
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Fred G. Martin <FREDM@nospamMEDIA.MIT.EDU>
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Viewed:
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949 times
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yes, memory wires should be oscillating, back and forth betw 0 and 5
volts. this is not floating; floating implies not connected.
re: your other DL probs, usually, it is a bad connection on the PCB.
try continuity checks on the memory subsystem. this is about 30 to 40
connections, a bit painstaking, but often it's not a bad chip, but a
bad connection on the PCB.
fred
> Fred-
> You left it unclear in an explanation to another letter. You were
> answering the fellow from India as to what readings one should see when usein • g
> a logic probe on the memory chip. You said that if one was stuck at 1 or
> zero-it might be indicative of a bad chip.
>
> Should be floating then-around 2.2 volts with power applied? Both red and
> green lights on when useing a logic probe?
>
> Also-I am still having downloading problems-I have had a HB that has always
> worked. Now it will not take a DL. I have replaced all the cables. I have
> ordered a new Maxamchip, & the three memory chips. Had I not spent the
> amount of money I did on the HB to begin with- I would have long ago given up • .
> Cappy Anderson, Yorki, ME
>
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Message is in Reply To:
 | | Readings
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| Fred- You left it unclear in an explanation to another letter. You were answering the fellow from India as to what readings one should see when useing a logic probe on the memory chip. You said that if one was stuck at 1 or zero-it might be (...) (26 years ago, 17-Jan-99, to lugnet.robotics.handyboard)
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