• Hello MLAers! We've re-enabled auto-approval for accounts. If you are still waiting on account approval, please check this thread for more information.

Another IIci ROM hack

You can remove the non-commercial restriction from Eagle Light by purchasing a $49 license. It still has the same board size restriction, though: http://www.cadsoftusa.com/shop/pricing/?language=en

There's also a $125 Eagle Hobbyist version, which has double the board size limit, but it's restricted to non-commercial use.

Beyond that, Eagle gets expensive pretty quickly if you're paying for it from your own pocket.

Among cheap/free Eagle alternatives, KiCad seems to have by far the most community support. I get comments on my blog every few days from people telling me what a dope I am for not using KiCad. :)

 
Oh thanks! I didn't see the $49 license when I was looking at their pricing. I think I can purchase the $49 license and rotate the SIMM socket 30 degrees or so. That way it fits on the board. It looks kind of funny, but it will work! That makes me happy because I've taken all this time to learn how to use EAGLE, and I'd rather not have to learn another one :-)

 
I've added a link to your index to the top post, dougg3. I'll add the index itself when I'm on a computer. It was too big for my phone's copy buffer, lol :)

 
I have to ask: who's gonna be the first person here to add a Formula 1 engine starting up for their boot chime on 3 or 4 Macs, then start them up so it sounds like the start of a race? :D *vrrooooom*

Edit: Woo! Page 18. :o)

 
Haha, that would be cool!

I am now a paid, licensed user of EAGLE (the basic $49 license) and I think I have a basic schematic for the programmer board pretty close to ready. I'm also awaiting an AVR USB development board. I may be able to do some basic testing with that before I have a board manufactured. So progress is slowly but surely being made!

My plan for now is to always be powered by USB, and I'm also leaving space to add a MAX232 RS232 transceiver. I'm probably going to skip the TTL and level shifter especially since USB will be standard. If someone really wants it, the pads where the MAX232 belong are available :)

 
Cool beans! I'm saving my pocket change!

I was thinking more along the lines of "Wipeout" or the "1812 Overture." :o)

"TAPS" for a death chime would be awesome!

 
So who's gonna be the first to play a practical joke, and set the death chime as the normal boot chime on some unsuspecting Mac user? ;)

 
LOL, I had mine that way when I was still learning how to use the ASC. Even though I knew it was there, it STILL freaked me out every time I booted it!

 
IIRC, there used to be an April Fools Day program/extension that'd do that without even mucking about in ROM.

It played the dead Mac tones and displayed the Sad Mac right after, or during, the bootup process.

If a co-worker was hammering on project with a ridiculous deadline . . .

. . . that was the best possible time to load it on their machine! }:)

 
Good news and bad news.

Good news: I got my SIMM and it's totally awesome. It's better than anything I ever expected.

Bad news: My Daystar Digital '040 upgrade doesn't like it. :( I get the Chime o' Death if I have both the custom ROM and my accelerator installed.

What I don't know is if the Daystar dies with any ROM installed, or if it's just the one I have. Maybe it's looking for a specific something or another? When I have the Daystar Digital installed, it does bring up its own custom Happy Mac. Maybe that's where the problem lies?

Looks like some investigating is in order. I'm may end up mailing dougg3 my upgrade card so he can barrow it and see if he can't figure out what's going on.

Edit: This just in: I didn't pull the ROM jumper on the motherboard. I'm gonna go try that real quick and see if makes any difference.

 
The ROM jumper most definitely has to be pulled in order for it to boot with the SIMM at all :)

When I have tried in the past to boot the IIci with my SIMM installed and the jumper installed, I'm pretty sure I didn't get a chime at all. The fact that you get a death chime at all with both the SIMM and jumper installed is weird...

 
Shoot. Pulling the jumper didn't change anything. Looks like an incompatibility with my accelerator card.

Weirdly enough, I hadn't pulled the Alternate ROM jumper when inserted the SIMM the first time, and it booted fine (that was without my accelerator.)

Edit: I also don't get a sad Mac or any error codes. It's a blank screen.

 
Hmm, but it does work when the accelerator card is removed? Also, something weird is going on if the jumper was installed and the SIMM booted OK. That shouldn't work. If it does work, something is wrong.

Sounds like the accelerator card is doing something weird. Maybe it patches the ROM somehow or something? When you're booted without the SIMM but with the accelerator installed and operating, let's look at the stored ROM checksum to make sure it matches the stock IIci ROM checksum. Hit the programmer's switch after you're booted. Type:

DM 40800000

And hit return. Let me know what the first 4 bytes are (first 8 hex digits). To get out of the debugger, type G and press return.

 
Last edited by a moderator:
That is the stock IIci ROM checksum...hmm. I was thinking if they changed the ROM they would have had to change the checksum too, to make the checksum test work. Or maybe they disable the checksum test altogether. I was just wondering in case the death chimes were caused by the checksum not matching. It's possible that the card is expecting to patch a stock ROM and when a patched ROM is present, it puts its own patches in that don't work, or something.

That's just a quick guess...this might be tough to figure out. The next logical step would be to put a stock IIci image on the SIMM and see if the update card boots with *that* present.

We should also figure out why your IIci boots from a custom SIMM when the ROM select jumper is inserted. Because it shouldn't....I'll test mine again just to make sure, but it really shouldn't work :)

Edit: mine works from the SIMM when the ROM select jumper is in, too. Maybe we're overpowering the internal chips or something? I would say that both the SIMM's chips and the DIP ROMs are fighting when their outputs differ, and the SIMM's chips are winning. I guess it works, but it's better to leave the jumper off whenever the SIMM is in :) Anyway, that knocks down item #2 I guess.

 
Just another idea, have you tried dumping the ROM using a ROM dumper app when booted with the upgrade card and comparing it to a stock IIci ROM dump (which you could get by booting from the IIci with neither the SIMM nor the upgrade card installed)?

If the Happy Mac is changing, I'm almost certain that there's some kind of ROM patching weirdness going on, as you said too. I'd like to see if reading the ROM shows any patches, or if it just reads the stock ROM. Either way, this is some weird stuff!

 
You must log in or register to reply here.

Similar threads

Boctor
Macintosh IIci DIP32 ROM replacement issues (SST39SF010A)
Replies
12
Views
2K
eharmon
eharmon
zigzagjoe
Macintosh 68060 Redux
4 5 6
Replies
103
Views
13K
croissantking
croissantking
F
Testers Needed: Modified ROM for LC475/Q605
2
Replies
38
Views
5K
frontein1
F
sircabulon
IIci/IIci/IIcx trouble
Replies
9
Views
2K
sircabulon
sircabulon
Jockelill
ROM hacking in the 68040 Macs
3 4 5
Replies
84
Views
18K
BobDaAggie
B
Back
Top