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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: Mrwoodchuck on July 08, 2016, 03:57:46 AM
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Hi all,
It's been awhile, that's what happens when you have kids I guess..
I'm trying to finish repairing one of my duo's, it had a dead cpu that was diagnosed by thesteve, "thank you!" and I had put it in storage and did not get back to it.
I pop in a hucard and it looks great, no issues.
(http://i.imgur.com/KyoW37Dl.jpg)
When I power it on with no hucard the cdrom menu is really messed up.
(http://i.imgur.com/B12MTcHl.jpg)
Currently the cdrom drive is not working because i need to replace vr105, so testing past the menu is not possible.
I was assuming the glitch was due to me replacing ic 520, apparently before I put it in storage when diagnosing the cpu I took out the ic but never put it back in. ](*,)
After looking at the datasheet I compared a sn74hc245 to this ic and I saw no difference, as such I used the sn74hc245 because I had some sitting on old parts boards.
(http://i.imgur.com/HN7mXWDlc4ca.jpg?1)
I tried 2 different chips, same results on both.
I was wondering if this could be a ram issue, or I should just buy the ALS245A from ebay?
Any input would be helpfull thanks all!