Re: TI-H: Expander SF
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Re: TI-H: Expander SF
>all i can tell you is that i had the same problem and i also tryed it on
>several ti85's.....and it wouldent work.
>when i asked mel he said it was a bad linkport....bullshit.
>it was a bad chip...i bought a new chip from someone switched it with my
>old one and every thing worked great.
Then that was probably a misconnection to the chip pins. Switch back
the old chip and I bet you some of the pins were bent inward and
therefore weren't fully contacting the PLCC socket.
If not, then send the chip back to me and I'll prove it...
I'm not trying to be the bad guy here! I have not seen a single bad
chip, ever. They don't just "go bad". When you've built over 70 of
them yourself you'll realize this.
The linkport connection is a very very crappy part of the TI-85. If
you use your linkport extensively, it is practically guaranteed to
fail. This happens to just about everybody. Since I use the linkport
extensively for many different things, they have failed on every TI-85
I've used. I know how to fix it however and I've replaced the
linkports on seven TI-85's (3 of which were mine). I would do this
when my expanders suddenly "stopped working." The slow-ass TI
protocol can handle inductively connected loads, but the Expander
operates 10 times faster so any slightly bad connection will screw it
up. I've mapped out the linkport circuit and determined some more
possible reasons why it won't work, but I'm still researching.
Since this is such a big issue I will have a linkport failure FAQ
about this on the release of the Expander II.
-Mel
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-The TI-Memory Expansion Homepage
-http://www.egr.msu.edu/~tsaimelv/expander.htm
References: