JrIDE Memory Corruption?

Hardware questions and modifications

JrIDE Memory Corruption?

Postby Tempest » Sat Dec 26, 2015 8:53 am

I've been having issues with my JrIDE and I think it's because the memory got corrupted somehow. If you read my previous thread (viewtopic.php?f=3&t=532) you can see I was having all kinds of problems getting my DOM to boot into DOS and was experiencing random crashes. Now I'm getting an ERROR A on boot up at the 128K mark (before I got this error at random points during the memory check). I think the memory in my JrIDE is bad. Is there a way to check this? Does someone offer repairs?
Omne ignotum pro magnifico

--- AtariProtos.com ---
The color of infinity inside an empty glass
Tempest
 
Posts: 305
Joined: Thu Jan 14, 2010 5:43 pm

Re: JrIDE Memory Corruption?

Postby Tempest » Sat Dec 26, 2015 9:13 am

And now it's working. Could it be overheating somehow? I was constantly getting that ERROR A at 128K about 30 min ago, but now after being off for a bit it's working fine.
Omne ignotum pro magnifico

--- AtariProtos.com ---
The color of infinity inside an empty glass
Tempest
 
Posts: 305
Joined: Thu Jan 14, 2010 5:43 pm

Re: JrIDE Memory Corruption?

Postby alanh » Sat Dec 26, 2015 4:38 pm

The most likely cause is either fatigue in the side car pins, unseating of chips, or the sidecar pins on the jride are wiggling out. Make sure everything is pressed in firmly. Might try racking the connector a couple times to ensure its snug. Some people have also added a small dab of solder to each pin to make sure they never wiggle out.
alanh
 
Posts: 250
Joined: Tue May 10, 2011 6:52 pm
Location: Atlanta, GA

Re: JrIDE Memory Corruption?

Postby Tempest » Sun Dec 27, 2015 3:47 pm

It could be I suppose but it was in a spare sidecar case and bolted to the main system. It really can't move anywhere. I took a look at it and none of the chips seem to be loose or anything.
Omne ignotum pro magnifico

--- AtariProtos.com ---
The color of infinity inside an empty glass
Tempest
 
Posts: 305
Joined: Thu Jan 14, 2010 5:43 pm

Re: JrIDE Memory Corruption?

Postby Tempest » Fri Jan 08, 2016 7:30 pm

New development. Now whether I'm using the DOM or regular hard drive the jrIDE says ERROR after scanning the drives. The boot menu never shows up. Is my jrIDE fried or could it be because I removed the floppy drive from the system?
Omne ignotum pro magnifico

--- AtariProtos.com ---
The color of infinity inside an empty glass
Tempest
 
Posts: 305
Joined: Thu Jan 14, 2010 5:43 pm

Re: JrIDE Memory Corruption?

Postby Tempest » Mon Feb 01, 2016 7:53 pm

Anyone?
Omne ignotum pro magnifico

--- AtariProtos.com ---
The color of infinity inside an empty glass
Tempest
 
Posts: 305
Joined: Thu Jan 14, 2010 5:43 pm

Re: JrIDE Memory Corruption?

Postby Brutman » Mon Feb 01, 2016 10:21 pm

Removing the floppy drive will give you an Error H, but the machine will still try to boot from an attached hard drive after pressing Enter to get past that error. Removing the floppy drive and controller is even more epic - the machine boots straight from the hard drive with no errors, and the BIOS reports that it has no floppy drives. So no, you removing the floppy drive is not the cause of the problem.

I defer to Alan on the hardware side, but until he corrects me here is what I would do:

  • Remove the jrIDE and everything from the system except the 64K memory card. Fire up the machine and use Ctrl-Alt-Ins to go into diagnostics. Let it sit there for a few hours counting the memory. If you get bored run the diagnostics on each component. The point of this exercise to to make sure the machine is somewhat sound.
  • Add the floppy controller and floppy drive back to the system. Keep it at 128K. Boot DOS 2.1 and run whatever memory testing program you can find to verify the first 128K is working. Let it loop for at least an hour. A memory tester program can't test the very lowest memory because the interrupt table, BIOS areas, and DOS are there but it is still better than nothing.
  • Inspect the jrIDE carefully with an eye loop or magnifying glass. Look for stray material shorting pins, tin whiskers from the solder, etc. Anything that might cause an intermittent connection is suspect. Reflow solder joints if necessary; cold solder breaks are a pain in the ass to find and you won't see them with a visual inspection. Be careful with the iron though; heat is good for solder but not components.
  • Reflash the BIOS and the CPLDs in case something is screwed up there.
  • Add the jrIDE back onto the system. Do not attach a device to it. Run the memory tester again. Let it loop for a long time.
  • If that all works, then you can try attaching devices again.

I haven't flashed the CPLDs in so long ... I need to look up how to do that again. (I'm sure Alan has it on a web page; I'm very behind here and I should have linked to his pages about a year ago.)


Mike
Brutman
Site Admin
 
Posts: 910
Joined: Sat Jun 21, 2008 5:03 pm

Re: JrIDE Memory Corruption?

Postby Tempest » Wed Feb 03, 2016 6:57 am

Thanks for the tips, I'll try these this weekend and see what happens.
Omne ignotum pro magnifico

--- AtariProtos.com ---
The color of infinity inside an empty glass
Tempest
 
Posts: 305
Joined: Thu Jan 14, 2010 5:43 pm

Re: JrIDE Memory Corruption?

Postby alanh » Wed Feb 03, 2016 11:53 am

I don't believe anything can be damaged on the board unless you took an ESD hit. Usually the resulting splash damage will cause hard rather than intermittent failures.

Re-seat all the chips. Consider putting dabs of solder on the side-car to PCB joints.

You can't reflash the CPLD unless you have an external cable. You would need either the official Atmel USB programmer ($$) or an Altera ByteBlaster II knock off from eBay/China (make sure it's the parallel port version). But a bit failure in CPLD flash would be a consistent error. It would not be intermittent. So that's highly unlikely. I can send you some replacement parts if you want to try an A/B swap until the issue follows a part? Send me your snail mail and I'll get them out this week.

-Alan
alanh
 
Posts: 250
Joined: Tue May 10, 2011 6:52 pm
Location: Atlanta, GA

Re: JrIDE Memory Corruption?

Postby MikeModified » Wed Feb 03, 2016 1:01 pm

Alan:

For future reference, could you provide a link to the files necessary to reflash the BIOS and CPLDs? Thanks.

Mike
MikeModified
 
Posts: 118
Joined: Sat Mar 15, 2014 5:10 pm
Location: Portland, OR

Next

Return to PCjr Hardware

Who is online

Users browsing this forum: No registered users and 2 guests

cron