SE/30 + dougg3 rom simm testing help requested

[bigmessowires]

If you've got an SE/30 and the dougg3 ROM SIMM (2MB or 8MB), would you help me test a modified version of the ROM image that I've developed? It works great on my IIsi and IIci, but not on the SE/30. I need help to find whether it's a software or hardware problem. The ROM image is attached. If you've got an 8MB SIMM, you can program this to the first 2MB of your SIMM and leave the rest empty.

Here's what you should get with this ROM image:

- customized startup sound (major 9th arpeggio)

- splash screen at startup displays installed RAM, addressing mode, and rom disk type

- compressed rom disk image containing System 7.1 and some games

- custom happy mac icon (in color!)

- memory test is disabled

- 32-bit clean

- HD20 support

At the splash screen, you can press R or A to boot from the rom disk, or turn it into a writable ram disk (decompresses on the fly, requires 1 MB RAM for decompression cache). Or press X to expand the entire disk image into ram. Or do nothing, and after a few seconds it'll boot from your SCSI drive or any floppy you insert.

On my SE/30, most of this doesn't work, and most of it fails in the same way as the "stock" romdrv0.9.6 from http://synack.net/~bbraun/macromboot.html. So I think either my hardware is bad, or there are serious incompatibilities between the SE/30 and the rom driver that are unrelated to my changes and additions.

- Booting from System 6.0.8 Tools floppy hangs at "Welcome to Macintosh". Occurs with both the BMOW rom image and the romdrv0.9.6 rom image.

- Booting from a Floppy Emu in HD20 mode (containing System 6.0. also hangs at "Welcome to Macintosh". Occurs with both the BMOW rom image and the romdrv0.9.6 rom image.

- Pressing R, A, or X at the splash screen hangs. (with BMOW rom)

- Holding R during startup boots successfully from the rom disk (with romdrv0.9.6)

FYI this rom image should also work on any of the other Macs that are compatible with the dougg3 simm, so feel free to try it. But it's specifically the SE/30 that I need some help with. Thanks!

2MB-fc2.zip

 

[olePigeon]

[butthead] This is the coolest thing I have ever seen. [/butthead]

 

[CC_333]

I have an SE/30 with a DougG3 SIMM, so I can give this a try (I've been meaning to check it out anyway, so this is a good excuse).

It'll probably be a few days before I get to it, but I'll try to do it this week.

c

 

[joethezombie]

I want to try it, but doug is out of stock and has been for some time. I've been patiently waiting

 

[techknight]

I have one, but no programmer.

 

[olePigeon]

It refused to boot when my DayStar Turbo 040 is installed.  If I pull my accelerator, it boots fine.

VERY cool, by the way.

Can the splash screen also be color?

 

[olePigeon]

This was on a IIci, by the way.  I haven't used it on an SE/30 yet.

 

[techknight]

well the SE/30 might have a slightly hard time displaying the color icons though. Just saying

 

[bigmessowires]

Cool, let me know if you (or anyone) gets a chance to try it on an SE/30 - that's where I'm really stumped. The color icons shouldn't be a problem, btw - SE/30 will display the B&W versions.

 

[bigmessowires]

And olePigeon, if you still have the iisi+romdrv0.9+nomem+nosum+img.bin in your SE/30 from your previous test, I'd be curious to know if it can boot from a floppy and/or and HD20. That's not working on my SE/30 with iisi+romdrv0.9+nomem+nosum+img.bin.

 

[olePigeon]

I'm currently drying the SE/30 motherboard.  I hope to have it recapped by this evening.  I can probably get to it tomorrow.

 

[CC_333]

I will also test, as it never hurts to have extra corroboration on matters such as this.

I'll try to get to it tomorrow or Wednesday evening.

c

 

[bigmessowires]

Thanks a lot. I'm pretty stumped on this one... I want to blame a hardware problem, but it seems a little too convenient. The SE/30 works fine with the stock ROM, as far as I can tell, but with my new ROM as well as the older romdrv0.9 ROM that olePigeon used, there are lots of problems.

 

[techknight]

I will be honest. Certain SE/30 boards are VERY picky about the Doug ROM SIMM. About 50/50 of them will boot and work with it. Why? Dunno!

 

[Macdrone]

I have an SE/30 that wont take an IIsi rom simm but the 30 simm works fine.  

 

[bigmessowires]

I'd still be grateful for reports from anyone who can try the ROM image from the first post in their SE/30. If you try it, I'd also like to know how much RAM is installed, and the brand and speed of the RAM SIMMs.

It's only a theory, but I think I partially understand what's going wrong, and why the Dougg3 ROM has been 50/50 in general with the SE/30. My hunch is it's not a physical problem with the SIMM or its thickness or anything like that, nor with the customizations for the ROM disk, but is a basic problem with attempting to use a IIsi ROM with an SE/30. The IIsi ROM seems to do RAM initialization differently than the SE/30 ROM, and the result is that some RAM configurations that work fine with the SE/30 ROM don't work with the IIsi ROM, or with anything custom that's derived from the IIsi.

I took a step back, and tried programming a stock IIsi ROM image to my SIMM and putting it in my loaner SE/30. That would rule out a problem with any of the customizations I've made - it's just a plain stock IIsi ROM image. It didn't work: boot chime, a few seconds of garbage video, then chimes of death. Then I programmed a stock SE/30 ROM image to the SIMM, and it worked fine. This seemed to rule out any physical problem with the SIMM itself, its thickness, etc.

So I went back to the stock IIsi ROM image, and tried changing the amount and configuration of RAM. I found that one set of 4 x 4MB SIMMs worked fine with the SE/30 ROM, but caused all kinds of problems with the IIsi ROM. Any RAM configuration that contained this set of 4 didn't work with the IIsi ROM. Any RAM configuration that didn't contain this set of 4 worked fine with the IIsi ROM. Using different SIMMs, I successfully booted with 4MB, 16MB, and 20MB. And I unsuccessfully booted with 16MB and 20MB. So it's not a question of the amount of installed RAM, but rather the SIMMs themselves.

You might think this just means that 4 x 4MB SIMM set was bad, except that:

1) it worked fine with the SE/30 ROM

2) Macdrone reported similar problems with a stock IIsi ROM in his SE/30, which otherwise works fine with the SE/30 ROM

So what is it about these 4 x 4MB SIMMs that the IIsi ROM doesn't like? That's where I need more testing help. The two obvious differences in my case are that the "problem" SIMMs are all 8 chip (no parity) while the others are 9 chip (with parity), and the problem SIMMs are a mix of 4 different brands and 3 speeds while the other sets are 2 or 1 brands and 2 or 1 speeds. I'm 99.9% sure the parity is irrelevant, so I'm looking at the mismatched SIMM types as the culprit. Could it be that the SE/30 ROM is somehow more tolerant of mismatched SIMMs than the IIsi ROM? Will reconfiguring the RAM convert a non-working Dougg3 SE/30 ROM into a working one?

 

[bigmessowires]

It looks like olePigeon concluded something very similar just five days ago, in an unrelated discussion about the SE/30, 32-bit ROMs, and RAM configurations: https://68kmla.org/forums/index.php?/topic/27686-se30-mode32-system-75-i-can-not-get-this-to-work/?p=295808

 

[olePigeon]

I've been stuck late at work this whole week, so I haven't gotten around to it.  Sorry.

 

[techknight]

Well RAM configuration is ruled out. I can rule that one out myself. 

I have 4MB of RAM I use for testing each SE/30 board that comes my way for repair. Some boot the doug ROM, Some do not. Same ram though!

And when I say dont boot, i mean completely dead. No chime, no anything.