Mac SE/30 - "Long Chime of Death" Start-Up Sound & Horizontal Stripes

[TheMightyMadman]

Hi all,

A few months ago, I bought my first Mac SE/30 sold-as-seen on eBay, figuring I'd take my chances on the condition of the battery.
I was unlucky this time, and the battery had bombed quite badly! The machine didn't make a start-up sound, and have horizontal stripes.

The original digital board wasn't really viable, so I bought a Bolle SE/30 PCB (fantastic work, Bolle and community!), and swapped the relevant parts over (including the ferrite beads on the rear of the board).
During this process, I socketed all of the DIP parts and the CPU, and have replaced quite a lot of parts too, including:

• All of the electrolytic capacitors (you know why).
• All three of the fuses.
• All eight of the RAM SIMM sockets (originals were poor quality).
• The ROM SIMM socket (original was battery damaged).
• The video ROM socket (original was battery damaged).
• The PDS connector (original was battery damaged).
• The RTC IC (swapped for an ATTinyRTC module), RTC crystal, battery holder, battery diodes (originals were battery damaged).
• The PAL ICs at UI6, UG6, UE6, UG7, UE7, UH7).
• The 74F258 RAM multiplexers at UI2, UI3, UI4, UJ2, UJ3, UJ4 (originals were battery damaged).
• The resistor packs at RP7, RP8, RP9 (originals were battery damaged).
• The 74F253 ICs at UA8, UB8, UC8, UD8 (originals hit by leaked electrolyte).
• The 74LS166 IC at UE8 (original hit by leaked electrolyte).
• The AM53C80 IC at UI12 (original hit by leaked electrolyte).
• The 8530 IC at UG12 (original hit by leaked electrolyte).

The current symptoms are now as follows: the machine gives a long "chime of death", and still only displays horizonal stripes.

The power supply and analogue board tested OK with another digital board (which I had on loan from a friend).
The ROM SIMM also tested OK, but that was a while ago now, and the traces look a bit suspect.
I have no idea if the RAM SIMMs are good - the machine gives the same symptoms with all the RAM SIMMs removed, and the same again with either of the two sets of four fitted in the lower four SIMM sockets only.
I've burned a 2764 EPROM for the video ROM (using the .bin file attached), but there is no change in symptoms with that or the original ROM.

Please see below pictures of the board:





I'm not really sure where to concentrate on next, so I would appreciate some advice if anyone has any!
What typically causes these specific symptoms?

• I'm pretty sure all of my soldering is OK, but I will check everything over again, the PLCCs in particular.
• UF8 was also quite badly hit by leaked electrolyte, so I may replace UF8 and UG8 (both 74LS393s).
• I'll try and check continuity on the pins/traces/vias on the ROM SIMM.

Many thanks,

Adam

 

[Bolle]

Is your GAL at UH7 a 25ns rated one? Try a faster one there. I'm not entirely sure what I used there for testing in the first place but I think it was an ATF16V8B-15. That's comparable to a GAL with a -10 speed rating, so I'd aim for that. Or try the original part from the donor board if it still has all legs
UH7 is involved with the RAM read/write as well as the RAS signals... slow chimes usually point towards a RAM problem, so this is where I'd start.

The rest of the board looks super clean, very nice soldering job.

 

[TheMightyMadman]

Is your GAL at UH7 a 25ns rated one? Try a faster one there. I'm not entirely sure what I used there for testing in the first place but I think it was an ATF16V8B-15. That's comparable to a GAL with a -10 speed rating, so I'd aim for that. Or try the original part from the donor board if it still has all legs
UH7 is involved with the RAM read/write as well as the RAS signals... slow chimes usually point towards a RAM problem, so this is where I'd start.

The rest of the board looks super clean, very nice soldering job.

Thanks Bolle, that's very high praise indeed, I'm glad you think so!

That's right, I'm using a programmed GAL16V8D-25LJN at UH7, I should have been more careful when choosing the part speed.

GAL16V8D-25LJN IC CPLD 8MC 25NS 20PLCC | eBay

IC CPLD 8MC 25NS 20PLCC.

www.ebay.co.uk

I swapped all of the original PAL chips across to the new board at first, including UH7, so they're all still intact/usable - I found that they were all running quite hot, UH7 in particular, so I decided to swap them out for new parts in case they were shorted/damaged. I didn't realise at the time, but I'd missed off L15 by accident, so at this point I wasn't getting any audio whatsoever, and the same horizontal lines.

I will try the original UH7 and/or a faster programmed GAL16V8D, thank you for the advice!

I'll keep you all updated as to any progress.

 

[TheMightyMadman]

Thanks Bolle, that's very high praise indeed, I'm glad you think so!

That's right, I'm using a programmed GAL16V8D-25LJN at UH7, I should have been more careful when choosing the part speed.

GAL16V8D-25LJN IC CPLD 8MC 25NS 20PLCC | eBay

IC CPLD 8MC 25NS 20PLCC.

www.ebay.co.uk

I swapped all of the original PAL chips across to the new board at first, including UH7, so they're all still intact/usable - I found that they were all running quite hot, UH7 in particular, so I decided to swap them out for new parts in case they were shorted/damaged. I didn't realise at the time, but I'd missed off L15 by accident, so at this point I wasn't getting any audio whatsoever, and the same horizontal lines.

I will try the original UH7 and/or a faster programmed GAL16V8D, thank you for the advice!

I'll keep you all updated as to any progress.

Hi again

I've swapped the original IC back into UH7, with no change in symptoms. I also have some faster GALs on order.
I've also tried some additional combinations of the various RAM SIMMs in the bottom four RAM SIMM sockets, with no change in symptoms.

In case it's of interest to anyone, here's what the original mainboard looked like!



Many thanks,

Adam

 

[TheMightyMadman]

Hi all,

I hope you're well

I've been continuing with this SE/30 board as and when I can, but unfortunately I'm not making much progress.

Testing with a known-good ROM SIMM and four known-good RAM SIMMs in the lower bank makes no difference - the machine gives a long "chime of death", and still only displays horizonal stripes. I've also replaced the resistor packs at RP1, RP4, RP5, and RP6 in case any of these were damaged, but again, no change. I've replaced the 74F240 at UD1 and the 74LS30 at UJ6 but again, no change. With UH7 removed, the board doesn't give any chime or display anything on the screen - with a new faster programmed GAL fitted at UH7, I still get the same symptoms as before.

Out of interest, what are the symptoms for an SE/30 where the RTC IC is not fitted or not working correctly?

Many thanks,

Adam

 

[igowen]

i was in your shoes (exact same symptoms) for a frustratingly long amount of time with my build. the root cause in my case did turn out to be poor connectivity on UH7, so that's probably where i'd start. specifically make sure that you're getting the expected clock signals out of the chip (C32M in particular), and that there is good connectivity between the legs of that chip and other spots on the board it's supposed to be connected to (the schematics are helpful here) -- the connections between UH7 and UE10, and between UH7 and the glue chip are of particular interest.

i found it *very* difficult to successfully solder UH7 because of its physical location on the board, and difficult to visually inspect for the same reason, so i ended up fitting a PLCC socket there (easier to hand solder once you cut the bottom out of it, since the pins are on the "inside") and continuity checking every pin of the socket and the rest of the board before inserting the chip.

don't lose heart! the fact that you're getting a chime at all means a lot of things are actually working. and honestly the fact that you were able to recover *anything* off of that battery bombed board is remarkable

 

[TheMightyMadman]

i was in your shoes (exact same symptoms) for a frustratingly long amount of time with my build. the root cause in my case did turn out to be poor connectivity on UH7, so that's probably where i'd start. specifically make sure that you're getting the expected clock signals out of the chip (C32M in particular), and that there is good connectivity between the legs of that chip and other spots on the board it's supposed to be connected to (the schematics are helpful here) -- the connections between UH7 and UE10, and between UH7 and the glue chip are of particular interest.

i found it *very* difficult to successfully solder UH7 because of its physical location on the board, and difficult to visually inspect for the same reason, so i ended up fitting a PLCC socket there (easier to hand solder once you cut the bottom out of it, since the pins are on the "inside") and continuity checking every pin of the socket and the rest of the board before inserting the chip.

don't lose heart! the fact that you're getting a chime at all means a lot of things are actually working. and honestly the fact that you were able to recover *anything* off of that battery bombed board is remarkable

Thank you very much, I appreciate the support and encouragement, nice work getting yours working again

I'm back working on my SE/30 again, trying to make any slow but sure progress.
Here's where I'm at now: it's making a slow, immediate "death chime", and the video RAM isn't getting reset (horizontal stripes).

I think this is a ROM access issue, as it's immediate at power-on and the symptoms don't change with all of the RAM SIMMs removed.
I'm testing with a known-good ROM SIMM, and the SIMM socket is a new good-quality part which seems to be installed correctly.

I've attached a picture below of where I'm at in terms of part testing:
- Green means new, confirmed to work myself, or taken off another less damaged board without change in symptoms.
- Blue means I don't think it could be related to my current issues.
- Orange means I think it could potentially be related to my current issues.

I've fitted a 1k resistor pack at RP9, which apparently should be OK; I've also fitted a HC rather than LS part at UE8.
I've went over the board many times over and I can't see any immediate issues with the soldering, even on the SOICs and PLCCs.

All power, data, and address lines on the ROM SIMM look good except for A15/A17/A18/A19, which always seem to sit around logic low - I need to check continuity on these with the other ICs. I don't think these four lines are associated with or driven by a different IC to the others which could be causing those ones to fail. I also need to test A0-A31 on the GLU IC. The ROM SIMM is being correctly selected. D15 looks a bit weird, but I don't really have a good reference point so that could be normal.

The select lines on the RAM multiplexers don't seem to be being driven, and are always high - pin 2 of UH7 is always low, pin 18 of UH7 is always high, pin 76 of the GLU IC is always low. This might be normal if the system is not yet trying to access the main RAM. The signals on UD1 all seem OK. The other signals on UH7 all look OK, except for "A WR" on pin 13 which looks a bit weird but that might be normal.

If anyone has had this issue before and/or could offer any advice, I would be very appreciative, as I just want my SE/30 to work at this point - I've thrown so many hours at it! Could video ROM access also be causing this problem, or would it just be the main ROM?

Many thanks,

Adam

 

[codevonlux]

Thank you very much, I appreciate the support and encouragement, nice work getting yours working again

I'm back working on my SE/30 again, trying to make any slow but sure progress.
Here's where I'm at now: it's making a slow, immediate "death chime", and the video RAM isn't getting reset (horizontal stripes).

I think this is a ROM access issue, as it's immediate at power-on and the symptoms don't change with all of the RAM SIMMs removed.
I'm testing with a known-good ROM SIMM, and the SIMM socket is a new good-quality part which seems to be installed correctly.

I've attached a picture below of where I'm at in terms of part testing:
- Green means new, confirmed to work myself, or taken off another less damaged board without change in symptoms.
- Blue means I don't think it could be related to my current issues.
- Orange means I think it could potentially be related to my current issues.

I've fitted a 1k resistor pack at RP9, which apparently should be OK; I've also fitted a HC rather than LS part at UE8.
I've went over the board many times over and I can't see any immediate issues with the soldering, even on the SOICs and PLCCs.

All power, data, and address lines on the ROM SIMM look good except for A15/A17/A18/A19, which always seem to sit around logic low - I need to check continuity on these with the other ICs. I don't think these four lines are associated with or driven by a different IC to the others which could be causing those ones to fail. I also need to test A0-A31 on the GLU IC. The ROM SIMM is being correctly selected. D15 looks a bit weird, but I don't really have a good reference point so that could be normal.

The select lines on the RAM multiplexers don't seem to be being driven, and are always high - pin 2 of UH7 is always low, pin 18 of UH7 is always high, pin 76 of the GLU IC is always low. This might be normal if the system is not yet trying to access the main RAM. The signals on UD1 all seem OK. The other signals on UH7 all look OK, except for "A WR" on pin 13 which looks a bit weird but that might be normal.

If anyone has had this issue before and/or could offer any advice, I would be very appreciative, as I just want my SE/30 to work at this point - I've thrown so many hours at it! Could video ROM access also be causing this problem, or would it just be the main ROM?

Many thanks,

Adam

View attachment 70991

Thank you very much, I appreciate the support and encouragement, nice work getting yours working again

I'm back working on my SE/30 again, trying to make any slow but sure progress.
Here's where I'm at now: it's making a slow, immediate "death chime", and the video RAM isn't getting reset (horizontal stripes).

I think this is a ROM access issue, as it's immediate at power-on and the symptoms don't change with all of the RAM SIMMs removed.
I'm testing with a known-good ROM SIMM, and the SIMM socket is a new good-quality part which seems to be installed correctly.

I've attached a picture below of where I'm at in terms of part testing:
- Green means new, confirmed to work myself, or taken off another less damaged board without change in symptoms.
- Blue means I don't think it could be related to my current issues.
- Orange means I think it could potentially be related to my current issues.

I've fitted a 1k resistor pack at RP9, which apparently should be OK; I've also fitted a HC rather than LS part at UE8.
I've went over the board many times over and I can't see any immediate issues with the soldering, even on the SOICs and PLCCs.

All power, data, and address lines on the ROM SIMM look good except for A15/A17/A18/A19, which always seem to sit around logic low - I need to check continuity on these with the other ICs. I don't think these four lines are associated with or driven by a different IC to the others which could be causing those ones to fail. I also need to test A0-A31 on the GLU IC. The ROM SIMM is being correctly selected. D15 looks a bit weird, but I don't really have a good reference point so that could be normal.

The select lines on the RAM multiplexers don't seem to be being driven, and are always high - pin 2 of UH7 is always low, pin 18 of UH7 is always high, pin 76 of the GLU IC is always low. This might be normal if the system is not yet trying to access the main RAM. The signals on UD1 all seem OK. The other signals on UH7 all look OK, except for "A WR" on pin 13 which looks a bit weird but that might be normal.

If anyone has had this issue before and/or could offer any advice, I would be very appreciative, as I just want my SE/30 to work at this point - I've thrown so many hours at it! Could video ROM access also be causing this problem, or would it just be the main ROM?

Many thanks,

Adam

View attachment 70991

Hi,

I have exact same problem as yours and it was a bad RP1 issue. (Check my post earlier) Yours should not be the same since you have a new PCB and RP1, but most likely RAM related. ROM should be fine in your case because it is actually code in the ROM running that playback the chime. Maybe trying a ROM-inator-II would give you a different behavior. It has a different algorithm on RAM testing.

Also check all the connectivity between SIMM contacts and their sources

Good luck.

-Yi