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Macintosh IIcx custom ROM

luRaichu

6502
Hi,
I'm looking for a IIcx compatible ROM that only has the memory test disabled and is 32-bit clean. The examples I've found include a ROM disk which I don't want or care for. Thanks
 
My IIcx is down for the count right now. But you can drop a IIsi ROM in the IIcx. This would give you a 32-bit clean ROM.

So really you probably want a IIsi ROM with just the memory test disabled (and vicariously the ROM checksum altered to not fail) right? If so give the attached a run (assuming you have a SIMM and a programmer handy)
 

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So really you probably want a IIsi ROM with just the memory test disabled (and vicariously the ROM checksum altered to not fail) right? If so give the attached a run (assuming you have a SIMM and a programmer handy)
Why is it double the size of a IIcx ROM?
 
Apple doubled the size of the ROM several times between 1986 and 1998, eventually ending up with 4MB ROMs.
68K Macs stopped at 2 MiB.

The first 1MiB ROM is probably this one:
Code:
067c.15f1    1991-10 - 420DBFF3 - Quadra 700 & 900 & PowerBook 140 & 170

These are the 2MiB ROMs:
Code:
067c.30f1    1994-05 - B6909089 - PowerBook 520 520c 540 540c
067c.30f2              B57687A5 - PowerBook 550c
077d.10f3.1  1994-09 - 5BF10FD1 - Quadra 660av & 840av
077d.2bf1.6  1995-08 - 4D27039C - Powerbook 190 & 190cs

Power Macs switched to 4 MiB to add all the PowerPC stuff.
3 MiB for the 68K part (includes PowerPC stuff that runs in MacOS).
1 MiB for the PowerPC part (ExceptionTable/Startup, HWInit, Nanokernel, 68K emulator, and Open Firmware for PCI Macs).
 
How do I split the ROM into 4 parts? I made my own ROM SIMM and am programming each chip manually
Either write a little Python program, or the program that comes with TL866 devices has a slice and dice option in the save window I think
If you're struggling, AI will walk you through it :)
 
AI will walk you through it :)
Thanks for slopping by

I found these commands here

srec_cat rom.bin -binary -split 4 0 -o U4.bin -binary
srec_cat rom.bin -binary -split 4 1 -o U3.bin -binary
srec_cat rom.bin -binary -split 4 2 -o U2.bin -binary
srec_cat rom.bin -binary -split 4 3 -o U1.bin -binary
 
Thanks for slopping by

I found these commands here

srec_cat rom.bin -binary -split 4 0 -o U4.bin -binary
srec_cat rom.bin -binary -split 4 1 -o U3.bin -binary
srec_cat rom.bin -binary -split 4 2 -o U2.bin -binary
srec_cat rom.bin -binary -split 4 3 -o U1.bin -binary
You... Do understand that there isn't a whole lot of difference between using a search engine to get someone else's solution... And using AI to explain how you do it?

Your irrational fear of software is really going to cause you issues through your life. "Sorry boss, I can't do my job because I refuse to use software that starts with the letter 'R', or that has green in the toolbar."
 
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look man, “ask AI” is a profoundly silly way to respond to luraichu’s question.
AI is particularly good, while poor at more nebulous questions, at responding to this type of "how do I" where the answer is a single, or few commands that take a little bit of structured thoughts to get right and are in a modern language / OS. It is actually a perfect example to see how it can be useful. I really actually hoped they would, so that they would learn that not everything in life is black and white, and sometimes things don't have to be perfect to be useful.

To be honest - I was surprised they were asking for help as it is only a little logic puzzle, but does take a few minutes of thought to get what goes where right.

It isn't an odd way to respond, as it is the fastest way to the answer and more likely to be correct than an answer from someone on the forum.

I have literally done what he was asking for in the past (without AI!) but to respond I'd either need to spend some time double checking how his board is wired, having a good old think about what bytes go where from the words, or 15 minutes digging through old folders looking for what I wrote before, on top of that, I'm also fallible - as are other people.

Think about the answer he got in the end - he just googled it. What kind of better response would you expect to have got from a hand crafted flesh computer response?

Also, I pointed him at some software with the functionality built in. But you both ignored that.
 
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