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talk about stress... not sure what’s next
Posted by: Slammbone1986 on 2020-10-22 19:22:56 Purchased my back-lit Portable 2 weeks ago off of fleabay knowing it wouldn’t turn on. Was informed he used the PowerBook charger for a while then it quit working altogether. Found out the battery was bad, put in a new battery and recapped the board. Just turned it on and this is my lovely welcoming message ugh. Anyone have any ideas? Anything would be helpful at this point.
Posted by: Slammbone1986 on 2020-10-22 19:29:31 Just reset it and got a new round of codes. The previous picture and this picture are the only ones I’m getting. Ideas?
Posted by: desertrout on 2020-10-23 10:08:16 If I'm not mistaken, these are data bus errors so you've either got some bad traces or a bad RAM chip. or even just a solder blob one of the RAM pins... start with a close visual check of the static ram, see if anything's amiss, then start checking continuities. Did you wash the board?
Posted by: Slammbone1986 on 2020-10-23 15:29:45 No I did not wash it. I did a mediocre job on repairing 3 lifted pads while doing the recap. I haven’t gone over any of races or anything. Will be doing that this evening. Thanks for the advice. I haven’t checked any of the ram either.
Posted by: Slammbone1986 on 2020-10-23 15:50:53 Are there any board schematics floating around out there? It might make doing all this trace testing a tad bit easier.....
Posted by: desertrout on 2020-10-24 09:30:35 I believe they're part of this group: https://archive.org/details/Macintosh68kSchematics But if not I've attached them to this post. There's also these ones being ported to KiCad, along with an attempt to reverse engineer the power manager (though use with caution!): https://github.com/ppieczul/macintosh-portable And this is a helpful document as well: https://www.apple.asimov.net/documentation/macintosh/atp_macintoshportable.pdf View attachment Macintosh Portable Schematic.pdf
Posted by: Slammbone1986 on 2020-10-24 10:22:59 I believe they're part of this group: https://archive.org/details/Macintosh68kSchematics But if not I've attached them to this post. There's also these ones being ported to KiCad, along with an attempt to reverse engineer the power manager (though use with caution!): https://github.com/ppieczul/macintosh-portable And this is a helpful document as well: https://www.apple.asimov.net/documentation/macintosh/atp_macintoshportable.pdf View attachment 38248 Great. Thank you!
Posted by: Slammbone1986 on 2020-10-24 11:26:36 Now I need the pinout of the CPU GLU chip. I can’t find it anywhere online. Need to check the R/W line per Techknight. I know the pin 9 on the CPU but not sure where to put the repair wire on the GLU chip.
Posted by: desertrout on 2020-10-24 13:46:34 Now I need the pinout of the CPU GLU chip. I can’t find it anywhere online. Need to check the R/W line per Techknight. I know the pin 9 on the CPU but not sure where to put the repair wire on the GLU chip. Pin 10. CPU GLU is page 5 of the schematic
Posted by: Slammbone1986 on 2020-10-24 14:48:51 Got the patch wire on CPU to GLU and the $E code is gone. Thanks @techknight and @desertrout for that one. It’s running a. It better now those guys have popped up. Not too sure what they mean.
Posted by: at0z on 2020-10-24 17:34:16 Got the patch wire on CPU to GLU and the $E code is gone. Thanks @techknight and @desertrout for that one. It’s running a. It better now those guys have popped up. Not too sure what they mean. View attachment 38263 View attachment 38264 I got the first of these which I think is a Ram test failure for onboard bank b, but still chasing that one.
Posted by: techknight on 2020-10-25 09:17:58 Probably have to inspect for open traces to the RAM ICs. They are a known weak point sometimes. I also have had the RAM go bad before, but only on 1 or two of the boards I serviced. Unfortunately, I am not accepting work at this time, because I will be flat out honest. I have no motivation to work on electronics much anymore as depression has rooted in to the point where now its become unhealthy. On top of this, the Pandemic set in, and I am in the high risk morbidly obese category so I am not taking any chances either. So I come online to try and help out where I can.
Posted by: Slammbone1986 on 2020-10-25 10:15:21 Well shit man in sorry to hear all of that. But I did get it going....sort of. I removed the ram expansion card and it’s fired right up into the OS using the stock Hard disk. But then after about 3 seconds I get a message that says there is not enough power to sustain memory and it shuts off after 10 seconds....very weird. But you had def helped me. That patch wire worked great just so you know.
Posted by: rplacd on 2020-10-25 10:32:26 Unfortunately, I am not accepting work at this time, because I will be flat out honest. I have no motivation to work on electronics much anymore as depression has rooted in to the point where now its become unhealthy. As someone who struggles with depression and anxiety, I just wanted to reach and say that we're all here for you – you give us and this community so much, I've learned so much from reading your posts. I know we'll see ya at your best some time in the future!
Posted by: Slammbone1986 on 2020-10-25 10:36:19 As someone who struggles with depression and anxiety, I just wanted to reach and say that we're all here for you – you give us and this community so much. I know we'll see ya at your best some time in the future! Well said. I just stared on here, but from what I have gathered in my short time, I’d that you had helped a loooot of people and best on here. Hope you get to feeling better sir!!
Posted by: LaPorta on 2020-10-25 10:41:07 Same goes here. I'd never have gotten my Portable up and running without @techknight's assistance. We have all been there through difficult times in our lifes, and I believe many of us are having some of the most difficult now with COVID. Hang in there, and we are also here in what limited capacity we can be!
Posted by: Crutch on 2020-10-25 12:33:35 Best wishes to you @techknight ! Thank you for all your help so far!
Posted by: techknight on 2020-10-25 13:10:53 Thanks you guys for the words of encouragement! I appreciate it. Its hard especially for me because I have Aspergers and along comes with it, an Anxiety disorder. the anxiety triggers some delusional thoughts from time to time, and its not like I can turn my brain off and tell it to shut up. Anyways.... I did find some solice by transitioning into a slightly different hobby over the last year or two to keep my mind occupied. but im starting to run out of steam there as well. Only thing I know to do is take it a day at a time. each day. The unfortunate side-effect to that is not feeling like I have anything to look forward to or live for. Spinning my wheels essentially. Not really moving forward, but not really moving backwards. Just sitting and spinning throwing my days away, but at the same time being thankful god gave me another day on this planet. The brain is a strange thing sometimes.
Posted by: cheesestraws on 2020-10-25 13:20:00 Its hard especially for me because I have Aspergers and along comes with it, an Anxiety disorder. the anxiety triggers some delusional thoughts from time to time, and its not like I can turn my brain off and tell it to shut up. Anyways.... I also have both Aspergers and moderate-to-severe depression. All of your post is intensely familiar, so you are not alone, if knowing that helps. I don't have anything very useful to say, other than solidarity and sympathy to you.
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