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Paula Abdul and the Power Mac 8100/110

D

Dandu

6502
Hi everyone. After Doug's experiments with the Power Mac G3 easter egg, I looked into the one on the Power Mac 8100, which is linked to Paula Abdul. I found a thread on Google Groups explaining that it’s tied to version 1.1 of the PowerPC Enabler.

Paula Abdul Bitmap in 8100/80 ROM?

groups.google.com groups.google.com

So I searched for the file on DiscMaster and found it—there’s a Spanish version of the file, and it does indeed contain an image of Paula Abdul. There’s also a GestaltID reference to the “Paul’s Desk Machine” (ID 31). You can download it.

https://discmaster.textfiles.com/br...DT).image/Carpeta del Sistema/PowerPC Enabler

I installed System 7.5 with the correct Enabler on a Power Mac 6100 (I don’t have an 8100), but I couldn’t figure out how to make the image appear. The method described on Google Groups doesn’t work. I also tried modifying the ID using some tools, but that didn’t work either.

Can you help me ? Is there anyone with a 8100 @ 110 MHz ?
 

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I probably have a stock 8100/110 somewhere but I'd have to dig for it.

I have an 8115/110 with an overclock (to 120MHz) that's readily accessible though. Do you think the easter egg is linked to a gestalt ID or a ROM check? If so this machine may satisfy it.
 
Franklinstein said:
I probably have a stock 8100/110 somewhere but I'd have to dig for it.

I have an 8115/110 with an overclock (to 120MHz) that's readily accessible though. Do you think the easter egg is linked to a gestalt ID or a ROM check? If so this machine may satisfy it.
Click to expand...
Probably the gestalt ID. The ROM is the same for all the x100 Power Macintosh, i mean (i'm not sure)
 
Apparently PowerPC Enabler 1.1 (and the updated v1.1.1) was intended to support the speed-bumped x100 Macs (6100/66, 7100/80, 8100/100 and 110, and probably some clones), so I assume there was a ROM change between the original and speed-bumped models that made the Enabler necessary. It's possible that the relevant ROM is present in any of the speed-bumped models but I can't say.

I'll try to get an OE version of 7.5 on my 8115 soon. I have to dig up another hard drive to do it (I don't want to reformat the existing disk).
 
I have a 6100/66 MHz model. I will try to dump the ROM to verifiy that (and i have a Pioneer clone, with the 66 MHz CPU too)
 
The following Gestalt IDs are in that Spanish PowerPC Enabler 1.1's 'gbly' resource (identifiers thanks to http://www.rgaros.nl/gestalt/chapters/ch-06.html):
  • 12 (unreleased 8100/120?)
  • 40 (8100/110)
  • 55 (8100/100)
  • 47 (7100/80)
  • 46 (prerelease 6100/66?)
  • 31 (Paula's Desk Macintosh)
The actual 6100/66 gestalt ID ended up being 100 according to that same site, but it's not in the enabler's list. So maybe it only works on the speedbumped 7100 and 8100 models. We could also try hacking the enabler. I briefly tinkered with this in MAME but it froze. But I could tell it worked, because it changes the startup message to look like this if it loads:

1751551429390.png
 
I tried hacking the enabler so that my physical 6100/60's Gestalt ID (75) was in the list, but that caused it to hang at the Welcome to Power Macintosh screen just like I saw in MAME. It's probably because I have no idea what I'm doing with the enablers. It seems like what we need is for someone with a 7100/80, 8100/100, or 8100/110 to try that Spanish 1.1 enabler with System 7.5 and see if the "secret about box" easter egg shows the picture instead of the usual breakout game.
 
joevt said:
Can you also dump the machine ID at 0x5FFFFFFC ? Same for anyone with a 6100/7100/8100
Click to expand...

Do you have a fancy way to do this easily? When I do this in MicroBug on my 6100/60:

D0 @$5FFFFFFC

And then print out D0:

D0

I get:

A500A500

which doesn't seem right.
 
dougg3 said:
Do you have a fancy way to do this easily? When I do this in MicroBug on my 6100/60:

D0 @$5FFFFFFC

And then print out D0:

D0

I get:

A500A500

which doesn't seem right.
Click to expand...
I'm not sure. 5FFFFFFC is a physical address.
The result should be something like 0xA55A031x

Try these:
Code: 
DB 5FFFFFFC
DB 5FFFFFFD
DB 5FFFFFFE
DB 5FFFFFFF
DM 5FFFFFFC 4
DL 5FFFFFFC
 
joevt said:
I'm not sure. 5FFFFFFC is a physical address.
The result should be something like 0xA55A031x
Click to expand...

Thanks. I was being lazy and hoping I could do it without installing MacsBug (the example commands you provided don't work in MicroBug as far as I know) but I just bit the bullet and installed MacsBug.

DL 5FFFFFFC in MacsBug on my 6100/60 returns the same thing I was seeing with my example MicroBug command: A500A500.

Edit: Aha, but if I dump a byte at a time, it works correctly. Weird.

DB 5FFFFFFC = $A5
DB 5FFFFFFD = $5A
DB 5FFFFFFE = $30
DB 5FFFFFFF = $10

Edit 2: this machine has the 9FEB69B3 ROM.
 
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The 9FEB69B3 (77D/20F2) ROM should be the original PDMs and 9B7A3AAD (77D/23F1) in the speed bumps, I think. (It's possible later-production non-speed-bump machines also came with the newer ROM though).

The 9FEB69B3 ROM shows these 3 non-68K machines in UniRom.
[info 15010, vers 1] Box PowerMac 6100 decoder 15 (HMC) VIA mask 00000000 VIA match 00000000 ID 3011
[info 1506c, vers 1] Box PowerMac 8100 decoder 15 (HMC) VIA mask 00000000 VIA match 00000000 ID 3013
[info 150c8, vers 1] Box PowerMac 7100 decoder 15 (HMC) VIA mask 00000000 VIA match 00000000 ID 3012
 
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dougg3 said:
Thanks. I was being lazy and hoping I could do it without installing MacsBug (the example commands you provided don't work in MicroBug as far as I know) but I just bit the bullet and installed MacsBug.

DL 5FFFFFFC in MacsBug on my 6100/60 returns the same thing I was seeing with my example MicroBug command: A500A500.

Edit: Aha, but if I dump a byte at a time, it works correctly. Weird.

DB 5FFFFFFC = $A5
DB 5FFFFFFD = $5A
DB 5FFFFFFE = $30
DB 5FFFFFFF = $10

Edit 2: this machine has the 9FEB69B3 ROM.
Click to expand...
I think MicroBug should have a method to display memory.
https://developer.apple.com/library/archive/technotes/tn/tn1136.html#//apple_ref/doc/uid/DTS10002975
If it does it one byte at a time, then DM 5FFFFFFC should work?

The Copland Disk Based Open Firmware for NuBus Power Macs ( https://tinkerdifferent.com/threads/powermac-7100-and-linux.4368/post-38377 ) accesses this register one byte at a time to determine which Power Mac it is:

Code: 
true to ?pdm
pvr@ 10 >>
		 5ffffffc xb@
	8 << 5ffffffd xb@ or
	8 << 5ffffffe xb@ or
	8 << 5fffffff xb@ or
10 << or value cpu-id

" device-tree" device-name
" Power Macintosh" model
" AAPL,????" ?pdm if
	2drop
	cpu-id 10 >> 3 and case
		0 of " AAPL,6100"     endof
		1 of " AAPL,6100 EVT" endof
		2 of " AAPL,7100"     endof
		3 of " AAPL,8100"     endof
	endcase
then encode-string
" MacRISC" encode-string encode+
" compatible" property

Your machine would have compatible of AAPL,6100
I wonder if any machine would have compatible of AAPL,6100 EVT and what EVT stands for?
 
EVT is Engineering Verification Test, which is pre-final hardware. For whatever reason some EVT logic boards had different IDs and even boxflags/gestalt IDs from what shipped.
 
Arbee said:
The 9FEB69B3 ROM shows these 3 non-68K machines in UniRom.
[info 15010, vers 1] Box PowerMac 6100 decoder 15 (HMC) VIA mask 00000000 VIA match 00000000 ID 3011
[info 1506c, vers 1] Box PowerMac 8100 decoder 15 (HMC) VIA mask 00000000 VIA match 00000000 ID 3013
[info 150c8, vers 1] Box PowerMac 7100 decoder 15 (HMC) VIA mask 00000000 VIA match 00000000 ID 3012
Click to expand...
Do 3011, 3012, 3013 come from the machine ID register (5FFFFFFC)? Does there exist code to translate the register ID 3010 that @dougg3 reported to the 3011 that you listed?
 
joevt said:
If it does it one byte at a time, then DM 5FFFFFFC should work?
Click to expand...

I put my 6100 away for the night, so I can't quite remember what it was displaying with that command. It was crashing after displaying the first 4 bytes (no way to limit the DM command to 4 bytes). That's why I was trying a register read/dump with D0 instead. But yeah, sounds like hardware requires 1-byte reads on it based on what you and @Arbee have found, and what I've observed.

joevt said:
Does MAME report 3011 in the machine ID register for Power Mac 6100?
Click to expand...
Arbee said:
Correct.
Click to expand...

What I noticed in MAME is if I boot it up like this with 3011 as the machine ID into System 7.5, the Gestalt ID is 61, which isn't the normal 6100/60 gestalt ID. (I confirmed that on hardware, at least mine, it's 75 as expected).

I tried changing the machine ID to 3010 to match my hardware, but then MAME just has a black screen. I was trying to figure out how to hack MAME to emulate an 8100/110 so I could try the easter egg, but I quickly realized I was getting myself into something deeper than I have time to tinker with right now. Plus, PowerPC asm scares me. :)
 
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