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redruM69

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  1. I've got a ROM 01 IIgs in that fails diags with error 03011500. From what I can decipher, it appears to be a state register failure, bit 01, address 15. Not really sure where to go from here though. My gut tells me CPU or maybe RAM. Suggestions?
  2. Oh well hey! Even better! I didn't know it was updated.
  3. @alaska360: Your Mac Portable battery v3.0 model has a couple of minor errors that can cause slicing issues, and a weak print. 2 of the 4 corners on your outer box have disconnected shells, which caused those 2 corners to print as if they are free standing. I fixed it. STL download below. portabattery30(FIXED).stl
  4. I threw in the towel and shipped the board back to the customer. There's a point at which the time/money spent on diagnosis and repair exceeds the value of the board, and this is WELL past that. I was hoping to follow through to the end, but I have a stack of other repairs growing. Thanks for the info guys!
  5. No shorts between traces, or vcc/gnd found yet. I did poke at the address and data lines with a logic probe. All data lines show activity. All address lines show activity, except A0, and A15-A19 are held low while powered. They are not shorted to ground though. Is that typical behavior?
  6. ROM has been swapped numerous times with known good. Contacts are clean. I can give this a shot. I haven't logic probed anything yet. This is my SE test rig. Analog is in great shape. Yup, 4 known good SIMMs installed.
  7. Update. All 6 RAM mux chips replaced. No change.
  8. My next hunch is the UI2-UJ4 mux chips. Anybody concur?
  9. I have an SE/30 board in for repair that I just cant figure out. It's been recapped, and corrosion was minimal. It shows the attached pattern. No chime, although I do hear 2 distinct "clicks" from the speaker at time of chime. All address and data line and other traces have been checked between ROM, RAM, VROM, VRAM, and UA8-UG8. Known good RAM/ROM/VROM has been swapped in. All UA8-UG8 chips have been replaced. Where would you go next on this one?
  10. It's worth noting that although the Toshiba 74HC166D is a CMOS part, it appears to be TTL tolerant. It worked fine as a replacement in my case.
  11. ISSUE RESOLVED! Techknight, you may want to add this to your notes. It appears that Texas Instruments SN74HC166DRG4 is NOT a valid replacement for the the 166 shift register @ UE8. It causes the discussed artifacts. I swapped it out again, but this time with a Toshiba 74HC166D, and the issue completely resolved!
  12. Also, I have tried swapping all 5 PALs with known good.
  13. Sorry to dig up a dead thread. Techknight, did you ever find anything on this? I have precisely the same video bug, but cant seem to figure it out. Both VRAM's and UE8 have been replaced. Tested all traces to and from VRAM. I still get vertical stripes with a slightly abnormal disk icon. Looks identical to your screenshot.
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