Death chime and Simasimac on Mac SE/30

[Breathing]

Hi all,

Several weeks ago I bought on eBay a Mac SE/30 Showing SimaSimac signs... I know it's not wise to buy an known not working system but I can't find one of these SE/30 easily where I leave (Switzerland). Working system that can be find on eBay are just too expensive.

So I did roll the dice and hopped for the best...

The exterior of the machine was in a bad condition, but luckily inside the battery did not exploded (This was my main concern). Sure the motherboard was full of dust, but beside being a bit dirty it was looking fine.

​

Of course as you would expect all the capacitor did leaked, so I first cleaned the board

1. Removed all the electrolytic capacitor
   
2. Clean the motherboard again.
   
3. Finally I replaced the original capacitor with tantalum one (Expect for the axial capacitor and C6 since I couldn’t find tantalum capacitor that can be de-rated and would still fit the original footprint).
   
4. I tested the connection from the new capacitor to make sure they made good contact and none did a shortcut on other traces.
   
5. The ROM-SIMM the video ROM the CPU and all socketed IC  where reseated
   
6. 4 RAM Module where added
   
7. A new Lithium battery for the PRAM has been put in place
   
8. Bourns Filters where tested OK
   

 ​

​

(Without the capacitors)​

 ​

​

(With the new capacitors)​

Unfortunately the Mac did boot with the Chime of Death (normal speed not slow) and the SimaSimac pattern.

​

There could still be several issue that need to be checked but since I don’t own a second SE/30 I won’t be able to swap the ROM Video or the PAL IC.

Since I do own a Macintosh SE a Macintosh IIx and IIfx. I would probably be able to do the following:

1. Test the Analogue board/Power supply by usiung the one from the SE (But I seriously doubt this could be the problem)
   
2. Swap the 68030 CPU from the IIfx with this Mac SE/30
   
3. Check each connection from the ROM Simm to the CPU, same for the RAM and the Mux.
   
4. Use the ROM SIMM from the IIfx on the Mac SE/30...  is this possible?
   

In the mean time I have several question for you guys:

• On the board I can see that the Audio IC from Sony have corroded legs, but since I do hear the chime of death could I consider the audio part to be fine?
  
• I read that to clear the SimaSimac issue one could “pull” the audio IC by adding a 1k resistor between pin 7 and 15…  but since my audio works is this still relevant?
  
• How one would trouble shoot the VRAM?
  

Clearly I did not yet gone thru all trouble shooting step, but I hope I won’t have to replace SMD IC or VRAM since I don’t know where to source them thus this post to get other point of view and ideas to help me trouble shoot this.

Many thaks for you help!

 

[Bolle]

Check UD8, UE8 and UF8. They get drowned in cap goo and tend to die (UE8 especially) resulting in video issues.

Your audio IC is good. Besides putting out sound it is responsible for handling the reset line. If you are getting any chimes the system is coming out of reset just fine - no need to add a pullup resistor.

I would suggest you start by replacing UE8. (or test it in IC tester if you have one)

 

[Breathing]

Thank you Bolle for this quick reply!

I will check the UE8 closely today (testing connections and re-soldering it).

No I don't have an IC tester, but I do have a logic analyzer and a scope I guess I can try to spot signal patterns. I will check the UD8,UE8 and UF8 datasheet to try to figure out what I should expect.

Are you suspecting this chip because it is closer to the C7 capacitor or because the 74LS166 are more sensitive than the other ICs around?



Unfortunately it seems that the 74LS166 is hard to get from local supplier, I may have to order it from China and be very patient...  as well as very optimistic regarding the reliability of the chips solder on those web sites.

Do you think that swapping the CPU is unnecessary? (--> Chime of death means there is audio and thus CPU activity?)

 

[bibilit]

74HC166 can be located easily and are direct swap.

 

[Breathing]

Thank you.

Yes you are right. I just finalized the order from DigiKey in order to repopulate the board with "fresh" IC. Also I took the chance to get spare bourn filter.

If I'm lucky I will get the parts for Christmas ;-)

 

[Bolle]

because it is closer to the C7 capacitor

This

I usually get single chips from ebay. Not worth it to place a digikey order most of the time.

Also if you are located in Switzerland you might want to check out reichelt.de. Usually cheaper if you order from them over here in Europe.

They don't have all the stuff though sometimes.

 

[Breathing]

Thanks for the hints, I will have a look at reichelt.de.

I also know conrad.de or the swiss version conrad.ch.

 

[techknight]

Its not going to be UE8, or any one of those ICs, I guarantee that. 

the "stripes" is the initial state of the VRAM at the time of powerup. Each brand of VRAM have their own initial states thats why different brand VRAM used in the various SE/30 boards power up differently when the video circuits are not initialized by ROM. The fact that you have those stripes and they are being displayed properly without being broken up, rules out 90% of the video circuit including UE8. However, that does NOT rule out the PAL ICs entirely, as one of them is responsible for generating the System RAM R/W timing. 

You need to start looking at address/data/chip select lines between the GLU/CPU and the VIA/SCC/SWIM, RAM Muxes, etc. The 74F258 muxes are known to fail on these boards, you could start there. 

Also a persons depiction of Fast and Slow chimes could be subjective, without a sound sample I cant tell if its truly slow or fast. Fast chimes could be caused by any one of the VIA's control lines to the CPU, or its interrupt and control lines back to the peripheral ICs. 

Either way, when I used to work on SE/30 boards, 100% of the death chimes were always caused by RAM access issues. RAM itself, the traces, or the ICs involved therein. But you experiences may be different. 

the system not being able to access the SCC, SWIM or SCSI would not cause death chimes, it never has for me. Even the ASC, but if it could not access the ASC, you would not get sound at all. The fact that the ROM is not initializing the video means its crapping out really early in the boot process, and thats 99% RAM with the SE/30. 

If anything, and I mean anything at all is holding up the bus, you would get nothing. no chimes, no nothing. The fact that you get Chimes, and especially if those chimes are clear, rules out the bus. 

 

[Breathing]

[SIZE=12pt]Thank you very much Techknight for your extensive answer.[/SIZE]

[SIZE=12pt]I was wondering where would the "zebra" pattern where coming from...  now I got the answer. VRAM default content.[/SIZE]

[SIZE=12pt]Yesterday I start looking at each and every trace on the board with a microscope just to see if corrosion where bellow the PCB coating layer.[/SIZE]

[SIZE=12pt]After more than 2 hours, the only thing I was able to "see" was the amount of oxidation on pads and IC legs! It's really horrifying when looking at them with such magnification.[/SIZE]

[SIZE=12pt] [/SIZE]

Then I started to check traces connection with my ohmmeter for the SWIM part, but this is a tedious work and I will need days to complete the complete board.


[SIZE=12pt] [/SIZE]

[SIZE=12pt]I was thinking of hooking a logic analyzer to the VRAM module and check the signals integrity (including data lines)..  this might help to speedup the trouble shooting time. Then I will trace back to the nearest IC if the signals are fine at this point.[/SIZE]

[SIZE=12pt][/SIZE]

Techknight, I will record the sound when booting, I will need to re-.-assemble the unit first. Also since I saw so much corrosion I will attempts another cleaning with long immersion of the board in hot water (I was only brushing on the surface and never submerge the board completely for a period of time (30 minutes should be fine to go beneath the ICs))


[SIZE=12pt][/SIZE]

[SIZE=12pt]Having a document that describe the boot sequence of this machine would be very handy for trouble shooting. Experience that I’m lacking to make educated guess regarding issues on such old system.[/SIZE]

[SIZE=12pt] [/SIZE]

 

[dochilli]

I had the same problem with my SE/30. After changing two of the F258 the problem was solved.

For cleaning you can use vinegar.

 

[Breathing]

So I received the IC's for replacement...  but before doing this task I wanted to do a second "vinegar" bath and warm water dipping therapy for the logic board.

After this I did let the board dry and reseated all the IC's ROM and SIMMs (Except for the RAM, I decided to use another set of four).

Finally I thought before doing any desoldering I will first record the Chime of Death for techknight so he could also provide valuable information about the speed of the chime (To me it sounded as a normal speed...).

I was completely shocked to hear the "Bong"! Not the Chime of death! The SE/30 was alive!



To conclude the main issue was

between the screen and the chair

I was so focused on the capacitors that where leaking all over the place that I didn't swap the RAM as a basic test...  I never realized that the RAM would be the cuprite on the Horizontal line symptom.

Here are the picture of the RAM (We can see "cracks" on the green protective layer on their PCB):





Honestly I’m happy that it was that simple to fix it..  but I’m also a bit disappointed, I was expecting to have more challenge on this little SE/30..  well,

the Hard drive is dead and the Floppy drive refuse to read my floppies so the restauration is far from complete but still.

Next steps will be to have a look at the analogue board and see if some capacitors needs to be replaced (Maybe the hard drive is fine but the +/-12V line is dead?), cleaning the Floppy drive and find a HDD replacement.

Thank you for your help and advice !

I have many more Macintosh to restore so it’s nice to see that the community is so active!

 

[Paralel]

Lucky you got one with a socketed CPU. Many people want those.

 

[techknight]

Told you it was RAM related. 

Whether it was the board or the RAM itself, thats what the bad chimes mean on an SE/30. 

I should have paid more attention, to the RAM that was installed in your board, I never had much luck with the through hole style RAM on a SIMM holding up to time. 

 

[captjon320]

Its not going to be UE8, or any one of those ICs, I guarantee that.

the "stripes" is the initial state of the VRAM at the time of powerup. Each brand of VRAM have their own initial states thats why different brand VRAM used in the various SE/30 boards power up differently when the video circuits are not initialized by ROM. The fact that you have those stripes and they are being displayed properly without being broken up, rules out 90% of the video circuit including UE8. However, that does NOT rule out the PAL ICs entirely, as one of them is responsible for generating the System RAM R/W timing.

You need to start looking at address/data/chip select lines between the GLU/CPU and the VIA/SCC/SWIM, RAM Muxes, etc. The 74F258 muxes are known to fail on these boards, you could start there.

Also a persons depiction of Fast and Slow chimes could be subjective, without a sound sample I cant tell if its truly slow or fast. Fast chimes could be caused by any one of the VIA's control lines to the CPU, or its interrupt and control lines back to the peripheral ICs.

Either way, when I used to work on SE/30 boards, 100% of the death chimes were always caused by RAM access issues. RAM itself, the traces, or the ICs involved therein. But you experiences may be different.

the system not being able to access the SCC, SWIM or SCSI would not cause death chimes, it never has for me. Even the ASC, but if it could not access the ASC, you would not get sound at all. The fact that the ROM is not initializing the video means its crapping out really early in the boot process, and thats 99% RAM with the SE/30.

If anything, and I mean anything at all is holding up the bus, you would get nothing. no chimes, no nothing. The fact that you get Chimes, and especially if those chimes are clear, rules out the bus.

I have an SE/30 that I'm working on and have this same issue (death chimes), but with a vertical SimaSimac pattern on the screen.

Here is what I have done so far:

Recapped board, run through ultrasonic cleaner, baked, reseated all the chips.
Used a known set of four working RAM and ROM from another SE/30 and tried to boot.
Replaced all the 74F258 muxes on the board with new ones.

I have attached a picture of the screen to this post and a link to a 6 second audio recording of the death chimes that I get upon boot. I do not know if this is slow or fast, which is why I posted so I could learn.

New Recording.m4a

drive.google.com

I do not have a scope, I only have good soldering skills and multimeter so my options are limited I know.

I would appreciate any help going forward to try and get this running again.

 

[techknight]

That m4a does not open on my phone, so I will have to look at it later

 

[drmadison]

That's the same chime I got yesterday when I didn't have the rom-simm installed properly (swapping between 32-bit clean and original for A/UX...)

 

[captjon320]

That m4a does not open on my phone, so I will have to look at it later

Were you able to open the sound file?

 

[techknight]

Were you able to open the sound file?

Nah i haven't come back to this thread yet until now, been busy. And no, I have not as I am typically on my mobile more often these days.

 

[captjon320]

That m4a does not open on my phone, so I will have to look at it later

View attachment Death Chime.mp3

Ahh, I should of done this earlier. Here is the death chime converted to an mp3 file for all to hear.

 

[techknight]

View attachment 40050

Ahh, I should of done this earlier. Here is the death chime converted to an mp3 file for all to hear.

Slow chimes. Can't see the RAM properly.

Could be the 253s, or broken traces