Mac IIcx no chime after board re-cap and startup circuit repair

[rodders]

I've installed a BlueSCSI successfully so I'm not dependent on floppies now. Writing the disk images to the SD took AGES!

I'm slowly getting to grips with MacOS and its foibles. I'm running 7.5.3 but only have 4MB of RAM and the OS takes over 2MB! This means lots of things won't run. Any suggestions for slimming it down would be helpful, I guess removing extensions would help but knowing which to get rid of is a bit beyond me at the moment.

I'm also learning that Stuffit isn't the most compatible software in the world, you need to know the version that stuffed the file and if its a later version you may not be able to unstuff it. Doh!

I've run MacTest Pro and everything seems to check out fine, which is gratifying.

SpaceQuest runs, if a bit slowly.

I guess 4MB isn't really enough for System 7, suggestions on what to upgrade would be useful. Going beyond 8MB seems fraught, either needing Mode32 or 32bit clean ROMS. Are there 32bit clean ROM images available or would I need to go to a ROMSIMM? I could add some virtual memory but that's going to thrash the SD card.
I've bought a couple of VRAMs for the graphics card as you suggested. I guess I need to hook up to a more capable monitor to take advantage of them (not obvious if there is any benefit with the Apple RGB monitor).

Sorry, that was a bit of a ramble but I'm still feeling my way...

 

[phipli]

Any suggestions for slimming it down would be helpful, I guess removing extensions would help but knowing which to get rid of is a bit beyond me at the moment.

Slimming down to 4MB would be going back to Mac OS 7.0.1 (uses about 1MB with a light install if I remember) or even 6.0.8 (uses hardly anything at all - way less than a MB)...

But 4MB is abnormally little for a IIcx, you probably should bump it to around 20MB (4x 1MB SIMMs + 4x 4MB SIMMs) for a sensible retrospective experience, but 8 is an absolute minimum really. Yes, they shipped with less, but the thing is there is a lot of much newer software that does work on them and you'll be able to run much more of it if you have more memory.

I'm also learning that Stuffit isn't the most compatible software in the world, you need to know the version that stuffed the file and if its a later version you may not be able to unstuff it. Doh!

Yes... really the issue is that people keep uploading software for old macs compressed using vastly too new versions meaning you can't decompress on the target machine. It... is infuriating. What I tend to do is decompress and recompress in an emulator before I move it over. I'm sorry, it really isn't beginner friendly and in fact, absolutely sucks.

Version 5.5 should run on System 7.5.3... that deals with most files. But if you're about to downgrade to an older OS (and considering your current RAM), you'll need version 4, or even 3.somthing.

I've run MacTest Pro and everything seems to check out fine, which is gratifying.

Excellent news!

I guess 4MB isn't really enough for System 7, suggestions on what to upgrade would be useful. Going beyond 8MB seems fraught, either needing Mode32 or 32bit clean ROMS. Are there 32bit clean ROM images available or would I need to go to a ROMSIMM? I could add some virtual memory but that's going to thrash the SD card.

This isn't the issue it sounds on this machine. On older machines it was a genuine nightmare, but with this, you just get SIMMs that fit - even PC ones mostly (almost always) work as long as they're 30pin (it technically doesn't even care if they are parity SIMMs, although the parity can't be used). Then you install MODE32 and switch it on in two places. If any of the things aren't fully set up, it doesn't matter, so there isn't a critical order or anything - the machine will boot regardless (as long as the RAM is good and the contacts are clean). Its no worry. There is even another extension that someone made that automatically switches 32bit on if it finds it isn't already set (handy if you don't have a battery retaining the setting as the machine will default to 24bit). https://github.com/cheesestraws/Force32 )

I've bought a couple of VRAMs for the graphics card as you suggested. I guess I need to hook up to a more capable monitor to take advantage of them (not obvious if there is any benefit with the Apple RGB monitor).

You should be able to use more colours - up to millions of colours (24bit) - even on that monitor. But it will be slow, so consider it like... a "preview" mode and you'll want to spend most of your time in 256 colours. Note actually, sometimes you might even want to set it to black and white because the display runs much faster then. I use black and white on my IIcx when I'm using music score software because you can get reasonable live scrolling in black and white and... not in 256 colours!

Check in the "Monitors" Control Panel if "Millions" of colours is already there. If you do want to use the IIcx with a more modern VGA monitor, you'll need a special adapter. Sadly they're about £20 these days, but there are designs for home made ones and to be honest, you could design your own, they're fairly simple. You're again lucky to have that specific video card because it is much more compatible with VGA monitors than the older common card that usually comes with the IIcx was. The older model predates VGA existing and needs very specific adapters to deal with the sync differences.

BTW - Your monitor looks like it is either set too bright, or more likely, might need a bit of maintenance. That blue colour cast shouldn't be there.

Sorry, that was a bit of a ramble but I'm still feeling my way...

Looks like you're doing pretty well to be honest Your patience getting the machine running was refreshing.

Looks like I'm rambling too, but feel free to ask anything, no matter how trivial. I realise it can be a nightmare to find information these days if you don't already know what terms to search for.

 

[rodders]

Version 5.5 should run on System 7.5.3..

I have 5.5 but when trying to unstuff MacTest I ended up with a partial .sit. Fortunately I found a MacTest CD iso file and used that instead.

Then you install MODE32 and switch it on in two places.

Which two places?

Check in the "Monitors" Control Panel if "Millions" of colours is already there

I did look but I didn't see it.

If you do want to use the IIcx with a more modern VGA monitor, you'll need a special adapter.

I have a GBS-C which I was planning to use.

That blue colour cast shouldn't be there.

I don't remember it being there in real life. I haven't tweaked the monitor at all. I'll try tuning it with the patterns in MaxTest Pro.

feel free to ask anything,

Many thanks for that.

 

[phipli]

Which two places?

In the Mode32 control panel itself, then go to the Memory control panel and switch it from 24 to 32bit addressing - you then need to restart. It will forget that setting if you power down without a battery, but will otherwise remember. The only real difference you'll generally notice is that in 24bit addressing mode, your RAM will be capped at 8MB (in About this Macintosh it will show all RAM above 8MB as being allocated to the Finder (a white lie)). A small amount of older software isn't compatible with 32bit addressing - the only one I can remember is one called LetraStudio... but that is an obscure program that we just happened to have when I was a kid.

I did look but I didn't see it.

Hum. Might need to install 32bit Quickdraw on the IIcx, or it might not be compatible because the ROM only has an older Quickdraw, but I suspect installing the extension will get it working... erm... it comes with Mavis Beacon Teaches Typing version 2.x... I remember that

Here is a copy : https://macintoshgarden.org/apps/apple-color-disk-32-bit-quickdraw-laserwriter-6

I have a GBS-C which I was planning to use.

Technically you don't need anything that fancy to get to VGA - it is capable of outputting a VGA compatible signal, the problem is just that you need to set the sense wires to tell the card what "monitor" is connected so it outputs the correct signals and the OS knows what it should do. You wouldn't hugely gain on the compatibility side with that box, you'd still need to make a physical adapter and rig something up to set the sense wires, it would just give you scaling etc (which I tend to leave to my monitors - I keep a few older VGA LCDs with 4:3 about for old computers).

It doesn't have the refresh issues that you get on other old non-PC systems, what is it? 14khz? Whatever it is.

I don't remember it being there in real life. I haven't tweaked the monitor at all. I'll try tuning it with the patterns in MaxTest Pro.

Interesting, the camera must have just picked it up more. If you can't see it that sounds alright.

Many thanks for that.

No problem

 

[phipli]

I have 5.5 but when trying to unstuff MacTest I ended up with a partial .sit.

That may be a lack of RAM to be honest. Stuffit isn't the best at throwing actual error messages and tends to just give up and quit.

 

[phipli]

Hum. Might need to install 32bit Quickdraw on the IIcx, or it might not be compatible because the ROM only has an older Quickdraw, but I suspect installing the extension will get it working... erm... it comes with Mavis Beacon Teaches Typing version 2.x... I remember that

Here is a copy : https://macintoshgarden.org/apps/apple-color-disk-32-bit-quickdraw-laserwriter-6

Yes, confirmed that you need to install 32bit QuickDraw.

Little brochure for the card (and its alternative that is identical except that it ships with 1MB pre-soldered). Yours is the 4.8, but upgraded to the 8.24 due to the VRAM SIMMs.

 

[rodders]

I seem to have tied myself in knots. I've created a new SD card for the BLUESCSI but when I boot from it I get blocking dialogs like this:

Please unlock the disk "xxx" and try again. The desktop couldn't be created.

If I cancel it it just pops up again, I can't even shut down properly. I assume there is something in the PRAM about disk xxx which isn't on this SD card. I've attempted resetting the PRAM with option, command, p,r but it doesn't seem to work.
Might have to resort to pulling the battery out.

Hmm, it just occurred to me that the p and r should be caps. I'll try that later when I get home.

 

[phipli]

I seem to have tied myself in knots. I've created a new SD card for the BLUESCSI but when I boot from it I get blocking dialogs like this:

Please unlock the disk "xxx" and try again. The desktop couldn't be created.

If I cancel it it just pops up again, I can't even shut down properly. I assume there is something in the PRAM about disk xxx which isn't on this SD card. I've attempted resetting the PRAM with option, command, p,r but it doesn't seem to work.
Might have to resort to pulling the battery out.

Hmm, it just occurred to me that the p and r should be caps. I'll try that later when I get home.

That issue is entirely to do with the disk image, not PRAM. PRAM only holds info on which device to boot related to this.

I recommend starting from a stock bootable image and working from there. It just sounds like the image is mounting locked for some reason, but that is a bit of a weird issue. I don't expect you can fix it on the IIcx, you'll want to fix it on your modern computer by replacing the image file, or possibly fixing it.

My guess is perhaps you have it set up in a way that the bluescsi thinks it is a CD? Have you named it correctly? Is it an ISO instead of a hard disk image? Have you used SCSI ID3 (which is the default for a CD - I don't have a bluescsi but there is a remote chance it assumes ID3 is a CD).

 

[rodders]

It boots into 6.0.8 ok but is trying to mount disks that aren't there. I'll try a different image and see if that helps.

 

[phipli]

It boots into 6.0.8 ok but is trying to mount disks that aren't there. I'll try a different image and see if that helps.

Sounds like there is a/are file/s on the card that it is trying to recognise as an image.

Check the log file to see what files it is trying to mount as disk images.

If that isn't possible for some reason (I don't have a bluescsi) remove any files you have added other than the disk images you want and check for invisible files your OS added and delete them (probably best from the command line with all windows for the SD card closed).

 

[rodders]

It seems like a bit of a gotcha that you're locked into a cycle of blocking dialogs. I presume that there is a way to break out of it but it's beyond my primitive macos skills.

 

[phipli]

It seems like a bit of a gotcha that you're locked into a cycle of blocking dialogs. I presume that there is a way to break out of it but it's beyond my primitive macos skills.

It isn't a period issue, this is a BlueSCSI thing.

Effectively it is presenting something as a locked disk that isn't a disk, so the OS is seeing something incorrectly formatted, that it can't correct. You can force things to not mount... but this absolutely needs to be sorted from the SD card world, not the classic computer world.

I suspect it is trying to eject it to solve the problem, but it keeps been "re-inserted" by the bluescsi. Guessing. Again, I don't have a blueSCSI. I'm old fashioned and tend to use spinning rust - I bought plenty of them before they went expensive.

 

[rodders]

I think I've sussed it. I thought the BlueSCSI only tried to mount images in the root but it seems to be trying to also mount cd images in a folder that have the same SCSI Ids as mounted disks. I'll fix it when I get home.

 

[rodders]

Hmm, I changed the BlueSCSI setup and it got rid of the loop of death but MacOS still complained about unlocking the disk. I think the problem may be due to me loading 7.5.5 and accessing CD-ROMs and then rebooting with 6.0.8 which is complaining because there are items in the desktop that it can't load (no CD-ROM extension).
Anyhow, I started again and have built a 7.5.3 drive by installing from scratch.

Thinking I was done messing with SD cards I put the lid back on and put the monitor on top. The next time I tried to boot it would either hang at the happy mac logo or the Welcome to Macintosh screen. Booting from floppy (6.0.8) worked but the mouse was erratic, suddenly jumping about as I moved it. I lifted off the monitor again, opened the lid and took out the SD card to read the BlueSCSI log but there was nothing untoward. Popped it back in and it booted up fine from the BlueSCSI. Curious as to why it should only fail with the lid on I replaced it with th machine running and the mouse became erratic again. Lifting the lid I tried pressing down on the PSU and sure enough, erratic mouse! The only thing I can think is that the lid presses on the PSU which causes the logic board to flex and open a broken trace - that's going to be fun to find.

Does anyone have experience of the lid pressing on the PSU like this? How tight is it usually?

 

[phipli]

Hmm, I changed the BlueSCSI setup and it got rid of the loop of death but MacOS still complained about unlocking the disk. I think the problem may be due to me loading 7.5.5 and accessing CD-ROMs and then rebooting with 6.0.8 which is complaining because there are items in the desktop that it can't load (no CD-ROM extension).

Ah, now that is an issue I know. The issue is that the filesystem changed a little between System 6 and System 7 - your System 6 is trying to rebuild the structure of the filesystem on the disk formatted for newer OSes, but the disk is locked, so it is failing. For CDs this was an issue with using newer disks with older systems... but there is a fix. Just install this extension in System 6 :

https://macintoshgarden.org/apps/desktop-mgr-201

Thinking I was done messing with SD cards I put the lid back on and put the monitor on top. The next time I tried to boot it would either hang at the happy mac logo or the Welcome to Macintosh screen. Booting from floppy (6.0.8) worked but the mouse was erratic, suddenly jumping about as I moved it. I lifted off the monitor again, opened the lid and took out the SD card to read the BlueSCSI log but there was nothing untoward. Popped it back in and it booted up fine from the BlueSCSI. Curious as to why it should only fail with the lid on I replaced it with th machine running and the mouse became erratic again. Lifting the lid I tried pressing down on the PSU and sure enough, erratic mouse! The only thing I can think is that the lid presses on the PSU which causes the logic board to flex and open a broken trace - that's going to be fun to find.

Hum, yes, that sounds like a dry joint. I'd check around the Via(s) and the ADB chip. Poke them with your finger while wiggling the mouse to see if you can narrow down which chip it is. I'd start with the ADB chip... I think the VIAs aren't going to be involved, I'm just mentioning them because one of them does some interrupt stuff that might be involved but... I forget that level of detail about how mouse / ADB stuff happens.

Actually, if it is something messing up interrupts the mouse might be lagging because the mouse interrupt isn't running due to something else hogging the processor... but regardless, start by poking things to see which area of the board reacts.

 

[rodders]

I'd start with the ADB chip..

Yep, I've just been reflowing the pins on this chip. They were corroded from the battery leak so I had another go at cleaning off the crap first. I think it would be a good idea to do the VIAs too.

Actually, if it is something messing up interrupts the mouse might be lagging

The mouse isn't lagging, it sort of jumps backwards, usually just before you get to the button you want to press! Maybe something is corrupting the signal coming back. BTW I have made sure its clean inside and operation returns to normal with the lid off.