Mac OS 8.6 findings and ramblings

[LightBulbFun]

so over the past couple weeks I have been playing with Mac OS 8.6 and i figured id just post my findings

so to start the Mac OS 8.6 image im working with here is the as far as i know the last 8.6 image apple put out which was the image for the Sawtooth.

now my goal with it was to try and get it running on computers that shipped with 9.x so with that said here is what I found out.

The Mac OS ROM included with this image of 8.6 is different to later Mac OS ROMs in that it has a much more specific machine check that is run when loading from OF then later Mac OS ROMs (and in OS Xs BootX for that matter) see when the Mac OS ROM image or BootX is loaded in OF they run a small script at the start to check the "compatible" property in the Root of the open firmware device tree. now later Mac OS ROM images and BootX check just for the MacRISC, MacRISC2, MacRISC3 or MacRISC4 compatible property.

but this image of Mac OS 8.6s ROM image has a much more specific check in that it has a list of compatible Model identifiers in the compatible check rather then just a Generic overall machine class compatible check. so instead of checking if Just MacRISC or MacRISC2 is there it has a list of model IDs it checks for. and the machine IDs it checks for before counting to load if found or aborting if not found are. iMac,1 PowerMac1,1 PowerBook1,1 PowerMac2,1 PowerMac3,1 PowerBook2,1.

so on any of the machines the Sawtooth image of 8.6 would boot up fine. but if say you tried to boot it on a PowerBook G3 Pismo it would abort as it would go to check the compatible listing in OF and pull up PowerBook3,1 and abort as thats not in the compatible list. now I had to get around this the easiest way to do this was simply to change the PowerBook3,1 listing in the compatible property in OF to PoweBook2,1 for that boot session (it is possible to make it persistent but thats for another time)

so I did that and it low and behold Mac OS 8.6 started to boot on the Pismo however near the end of booting from the installer CD the machine would just turn off without warning so I took the HDD and manually installed 8.6 to the HDD and re did the above steps this time booting from HDD and it booted all the way to the desktop. I got 8.6 running on an unsupported and newer computer then it self

a couple quirks with it is it does not detect the battery (tho it runs off battery fine) and the Rage 128 drivers dont load (this one is probably solvable by installing newer ATI drivers) and finally another interesting thing I noticed was with a normal 8.6 install 8.6 does not recognise a 7410 CPU Properly but this sawtooth image on my Pismo has no problems knowing what to call the 7410 that I have fitted. (which is interesting as the 7410 had not yet come out when the Sawtooth went on sale but i would not be surprised if apple was already playing with engineering samples or the like)

I hope this all makes sense (im not very good at making proper forum posts ) its not meant to be a guide or anything just a post on my findings and that it is possible to boot Mac OS 8.6 on unsupported/newer Macs (I did try this on a 800Mhz Snow iBook G3 and it did not get very far before hanging sadly.) and I may go into greater detail in what i did at a later point.

 

[AphoticD]

Hey LightBulbFun, great work here. I think you may have the world's only OS 8.6 booting Pismo!

I recently acquired a gorgeous Pismo G3 400Mhz. I used spare parts from my upgraded TiBook to bring the specs up a little to 320MB of RAM and a 40GB 4200rpm HDD. (The PC133 SODIMM worked fine in a PC100 slot).

I have been trying to get Mac OS 8.6 to boot as per your notes. I took a slightly different route, but still can't get anywhere;

1. Prepared a clean "Universal" install of Mac OS 8.5 in SheepShaver.
2. Upgraded the install to 8.6.
3. Used Disk Utility in Tiger to "Restore" the Sheepshaver disk image onto a real partition on the Pismo's HDD.
4. Blessed the System Folder on the new Mac OS 8.6 partition (sudo bless -folder9 /Volumes/Mac\ OS\ 8/System\ Folder)
5. Selected "Mac OS 8.6" from Startup Disk System Preferences in Tiger.
6. Rebooted into Open Firmware (Cmd-Opt-O-F)
7. Used these OF commands to spoof the model identifier:

dev /
.properties
" PowerBook2,1" encode-string " model" property
" PowerBook2,1" encode-string " MacRISC2" encode-string encode+ " MacRISC" encode-string encode+ " Power Macintosh" encode-string encode+ " compatible" property
mac-boot

Unfortunately, each time it fails to even attempt to boot into 8.6 and shows just the flashing system folder for a few seconds before launching into a Tiger boot.

I have also tried booting into Mac OS 9.2.2, moving the Finder out of the 8.6 System Folder, putting it back in (to "re-bless") and then selecting 8.6 from the Startup Disk Control Panel, before restarting and re-applying the OF command.

I think your Mac OS ROM file from the Sawtooth could make all the difference here. Are you able to compress and upload a copy?

Thanks,
-AphoticD
[doublepost=1503405555][/doublepost]I am downloading an image of the Sawtooth restore disc named sawtooth_8.6_restore&Install.zip.

This may do the trick...

 

[LightBulbFun]

your OF commands like good, (I would recommend doing boot cd:,\\:tbxi instead of mac-boot. also keep in mind the OF changes are volatile ie they will reset once you reboot/reset the machine)

but you do need a Sawtooth 8.6 install, as thats the latest 8.6 image and contains the most up to date uninorth drivers. the install CD image i found on the internet is called sawtooth_8.6_restore&Install.zip

fun fact this also works on MDDs , one thing I have noticed, is the GPU you have installed in the machine can prevent the Mac OS ROM from loading properly. and I had to use the ATA33 keylargo bus (I cant remember if the ATA66 Keylargo bus worked) (I Know the ATA100 bus hanging off the U2 controller does not work in 8.6)
for an MDD, substitute PowerBook2,1 for PowerMac3,1 (I suspect 8.6 could also be made to work on GigE DA and QS G4s but i sadly dont own any of those)

 

[AphoticD]

Okay, I got it!

1. Downloaded and burned the Sawtooth G4 8.6 Restore & Install CD.
2. Used the Software Restore application on the CD while running under Mac OS 9 to copy the G4's restore image onto the Pismo's OS 8 partition.
3. Set the newly restored Mac OS 8.6 as the active Startup Disk.
4. Rebooted and used the OF commands to spoof just the "compatible" property to PowerBook1,1 (PowerBook2,1 refused to work for me)

dev /
" PowerBook1,1" encode-string " compatible" property
mac-boot

5. Mac OS 8.6 boots with a happy Mac and a desktop!
6. I copied all of the ATI and FireWire extensions from Mac OS 9.2.2 across to the 8.6 System Folder and rebooted again (applying the OF commands on each boot). With these extensions, we have full graphics acceleration and FireWire support. This part was easier than I expected it would be.

It's worth noting that although this is fun, it has caused the Pismo to run _very_ hot. I can see that the power saving / processor cycling software is not functioning properly regardless of my settings in Energy Saver.

I'll need to keep playing around with it, but I think power management is going to be at the (nano) kernel / ROM level and not something as simple as updating a control panel or extension file.

I haven't changed the thermal paste or pads yet, and the cooling fan doesn't seem to ever come on (maybe it's broken?). I shouldn't have been surprised as the room was starting to warm up as well, but all of the playing around started causing signs of the old Pismo overheating. First the memory test began to fail on each boot and then there were graphical glitches. I shut it down for 10 minutes, rebooted into Mac OS 9 and found everything was running cool again.

While both operating systems have Energy Saver set to "Better Conservation", the idle CPU temps as shown in Gauge PRO are;

Mac OS 9.2.2 CPU when idle 30°C
Mac OS 8.6 CPU when idle 46°C (Too high for a G3!)

I'm wondering if the PowerBook1,1 "compatible" property could be preventing the power management from running properly... @LightBulbFun, does your Pismo run notably hotter in 8.6?

 

[LightBulbFun]

Very cool to see you got it working too (I did not even know firewire did not work in 8.6, I never tested it in Mac OS 8.6 LOL)

I highly recommend you try and get PowerBook2,1 working, as that is the closest matching mac to a Pismo, (PowerBook2,1 and PowerBook3,1 are both Uninorth 1, Keylargo machines, where as PowerBook1,1 is a Gossamer/Heathrow machine) what sort of issues are you getting when you try PowerBook2,1?

in regards to overheating, I have not noticed any issues in that regard with my Pismo, and I Have run a Lot of OSes on my Pismo from Mac OS 8.6 to Mac OS X 10.5.8 and thats on top of the fact I have a 600Mhz 7410 soldered to my CPU Card (see here https://forums.macrumors.com/threads/making-a-g4-pismo-upgrade-at-home.2019269/ ), and im still running with stock cooling(save for removal of the old thermal sheet on the heatsink and an application of fresh thermal paste on the CPU). it takes a LOT of intensive work to get the Pismos system fan to turn on, if I, say play an intensive game of Quake 3 after like 20-30 minutes the little CPU fan will kick in and thats with a 600Mhz G4. its been rock solid stable for me (the pismo that is, I have not extensively used 8.6 on it)

(Speaking of I really need to order more 512MB PC133 SODIMMs my only one is currently sitting in a iBook G3 clamshell, its on the list of things i need that i never get round to ordering like some more solder wick so i can commence on the iBook G3 CPU swap )

what kind of CPU heatsink does your Pismo use? I have noticed that there are 2 types... I wonder if one is better then the other (mine is the type where all of it shiny, but theres another one where the main heatsink hanging off the heat pipe is a matt gray colour)

BTW I cant help but notice that your missing L2 cache in system profiler and that only 160MB of RAM is showing? do you see L2 cache when booted into Mac OS 9.2.2?/OS X, if not, do you get a pop up in Classic Mac OS mention Cache failure/does diagnostics in OS Xs system profiler mention cache failure? it might be related to your overheating issues, Also is your Boot ROM fully up to date? theres a surprising amount of machines where this is not the case, I highly recommend you update to the latest which would be 4.1.8f5 for the Pismo IIRC

in theory you should be able to edit the Mac OS ROM it self and avoid having to do any sort of OF hackery, but I have not been able to get this to work (following the guide for hacking the Mac OS 9.2.2 ROM, even replacing abort with clear it still halts on a checksum error for me)

I also should mention for the MDD to work in 8.6, Much like booting Mac OS 9.2.2 on a 7447/A/B or 7448 you have to fake the CPU PVR (processor version register) to one that was around when that OS was put out so in the case of Mac OS 8.6 I changed the 7455Bs PVR in OF to that of a 7400, this once again is volatile

 

[AphoticD]

Very cool to see you got it working too (I did not even know firewire did not work in 8.6, I never tested it in Mac OS 8.6 LOL)

Thanks! I made some further progress this morning.

I highly recommend you try and get PowerBook2,1 working, as that is the closest matching mac to a Pismo, (PowerBook2,1 and PowerBook3,1 are both Uninorth 1, Keylargo machines, where as PowerBook1,1 is a Gossamer/Heathrow machine) what sort of issues are you getting when you try PowerBook2,1?

Initially, I would get a message during boot saying that the software installation needs to be updated and it gave me a "Restart" option. I have since successfully re-run the PowerBook2,1 OF commands and it is booting OK. (Perhaps it was a first-boot thing).



I can confirm that Mac OS 8.6 is definitely causing thermal issues. On cold boot, Mac OS 9 gave me a temp of 22°C, I then set the Mac OS 8.6 as the Startup Disk, rebooted, entered the OF commands and booted to the 8.6 Desktop. Checking Gauge PRO showed a massive jump to 38°C within only a few minutes. I let it sit for a few minutes to see if it might drop, but it held it's place. Energy Saver settings are at Conservative and Processor Cycling is enabled in the control panel.


(Mac OS 9.2.2 running at 22°C after a cold start).


(Mac OS 8.6 after a reboot, hitting 38°C).

On next reboot (only a few minutes later), Mac OS 9 reported memory test failure at startup and the L2 cache was disabled.

I shut it down, let it cool, pulled it apart and re-pasted the CPU with silver and a new sheet of magic 2mm silicone thermal padding between the heatsink and the aluminum cage.

A reboot into 9.2.2 after the re-paste showed 22°C again. I am hesitant to boot back into 8.6 as I don't want to fry my new baby!

what kind of CPU heatsink does your Pismo use? I have noticed that there are 2 types... I wonder if one is better then the other (mine is the type where all of it shiny, but theres another one where the main heatsink hanging off the heat pipe is a matt gray colour)

It's the shiny aluminum type.

BTW I cant help but notice that your missing L2 cache in system profiler and that only 160MB of RAM is showing? do you see L2 cache when booted into Mac OS 9.2.2?/OS X, if not, do you get a pop up in Classic Mac OS mention Cache failure/does diagnostics in OS Xs system profiler mention cache failure? it might be related to your overheating issues, Also is your Boot ROM fully up to date? theres a surprising amount of machines where this is not the case, I highly recommend you update to the latest which would be 4.1.8f5 for the Pismo IIRC

Yes, the low RAM and missing L2 cache are a direct result of overheating while running OS 8.6. After letting it cool off for a few minutes seems to resolve it, but as I mentioned, 8.6 keeps causing it to overheat.

The Boot ROM is 4.1.8f5

I think I might just leave 8.6 alone now... I don't want to fry the little '750. I will however, use the partition to play around with Rhapsody DR2 and some versions of Kodiak. 10.0 DP2 looks really cool being a unique design hybrid of 9/X.

 

[LightBulbFun]

its been a while (I got a bit side tracked with other things)

but a while ago I managed to finally hack the Mac OS ROM from the 8.6 Sawtooth image so it would boot on unsupported machines without any OF fiddling I more or less applied the patches the User iMacC2D used on the Mac OS 9 ROM, to the Mac OS 8.6 ROM. (sadly it seems he has left MR and also removed all of his content from his thread on getting 9.2.2 booting on unsupported macs)

note tho that if you have a 7450 or newer you will still have to Fake the CPU PVR in OF to that of a Rev 2.7 7400.

to use it just image the Sawtooth install to a HDD and replace the "Mac OS ROM" file with this one

so far the machines iv tested it on:

Pismo will Boot OOB

Dual 1.42 MDD FW800 with FW400 BootROM will boot as long as you Fake the PVR and use the Key-largo ATA bus

Dual 1.42Ghz MDD FW800 with stock boot ROM. WONT boot this ROM sadly. (even with a Rage 128 PCI) still need to look into this some more.

and my SnowBooks (PowerBook4,1 and PowerBook4,3) and iMac G3 PowerMac2,2 wont boot the 8.6 ROM either strangely... im not entirely sure why these 2 wont boot seeing as the Pismo does, and the PowerMac2,1 is officially supported by 8.6

I have noticed that certain video cards can stop the Mac OS 8.6 ROM from booting. so that might be something to look into

I suspect GigE Cubes DAs and Quicksilvers would be able to Boot Mac OS 8.6 with my Hacked ROM (but sadly I dont own any of those machines to test the ROM on)

https://mega.nz/#!VUgFAKZR!xXTi_4BK2wJHU8QYCoqyNIjq2aZFPFnM7B4JlmY1lRk

(I also formatted the OP a bit so its not one massive wall of text. )

 

[AphoticD]

Nice work man! I'll have to try it out on the Pismo and the PowerBook3,2 (Mercury).

 

[forzamyro]

I found this thread a few weeks ago.
I have tried my Pismo 500Mhz to boot with using newly acquired "PowerMac G4 Software Restore CD". (See attached)
SSW version 8.6
CD version 1.2
J691-2461-A (Japanese)

1. Used the Software Restore application on the CD while running under Mac OS 9 to copy the G4's restore image onto the Pismo's OS 8 partition.
2. Set the newly restored Mac OS 8.6 as the active Startup Disk.
3. Rebooted and used the OF commands to spoof just the "compatible" property to PowterBook2,1.

0 > dev /
0 > " PowerBook2,1" encode-string " compatible" property
0 > mac-boot

4. Mac OS 8.6 boots with the "icon parade".... (See attached)
5. But suddenly turned off.

I also tried with the downloaded "Sawtooth G4 8.6 Restore & Install CD.iso".
It came up to the same result.

I don't know what the cause is. :-<

 

[LightBulbFun]

hmm yeah I ran into that issue a couple times, for me it always happened when trying to boot the CD

but if I restored the OS to a HDD then tried to boot from it, it generally booted up fine

id try a PRAM and PMU reset, also what is your battery situation like? might be worth trying with or without a battery installed

BTW I recommend you install the modified ROM I made above, so you dont have to continuously spoof your model identifier

 

[forzamyro]

Thank you for your quick reply.

I tried a PRAM and PMU reset, also with or without a battery situation.
But it came up to the same results.

Anyway I installed your modified ROM.
And checked with "Sawtooth G4 8.6 Restore & Install CD.iso".
I could skip the OF process but encountered a system error.





When I expanded the "8.6-hacked-Mac OS ROM.zip", there appeared the "Mac OS ROM" file with a blank icon.



(I changed its attribute, Type to "tbxi" and Creator to "chrp".)
Is it correct?

 

[forzamyro]

I have noticed that certain video cards can stop the Mac OS 8.6 ROM from booting. so that might be something to look into

Here is my Pismo's "Apple System Profiler".
Its PCI (video card) is "ATY,RageM3pParent".
Is it okay?

 

[LightBulbFun]

Here is my Pismo's "Apple System Profiler".
Its PCI (video card) is "ATY,RageM3pParent".
Is it okay?

View attachment 847816

Yeah thats fine

notice I said it stops the Mac OS 8.6 ROM from booting, meaning you would not even get into the OS if you had a video card that stopped things from working

but on that note, whats your BootROM version? Im running the latest 4.1.8 I recommend that you update to that version if you have not already

 

[forzamyro]

notice I said it stops the Mac OS 8.6 ROM from booting, meaning you would not even get into the OS if you had a video card that stopped things from working

Thank you for the easy to understand explanation.
I misunderstood that.

but on that note, whats your BootROM version? Im running the latest 4.1.8 I recommend that you update to that version if you have not already

Sorry for Japanese letters.
There is "BootROM version: $0004.18f5".

 

[forzamyro]

Again I will start from the "Sawtooth G4 8.6 Restore & Install CD.iso".
That contains ASR(Apple Software Restore) version2.0.5 and Mac OS ROM version2.5.1.
Is it correct?

 

[forzamyro]

There has been a little progress.
I unzipped the "8.6-hacked-Mac OS ROM.zip" on Tiger(OS X 10.4) to get a Mac OS ROM correctly.
Its icon is not blank this time.
I could skip the OF process and boot the Mac OS 8.6.
However, there occurred a power off after the icon parade again.

I tested Mac OS 8.6(Japanese version) and obtained the same results.

 

[LightBulbFun]

was just reading back through this thread and noticed i missed the last 2 comments my bad!

There has been a little progress.
I unzipped the "8.6-hacked-Mac OS ROM.zip" on Tiger(OS X 10.4) to get a Mac OS ROM correctly.
Its icon is not blank this time.
I could skip the OF process and boot the Mac OS 8.6.
However, there occurred a power off after the icon parade again.

I tested Mac OS 8.6(Japanese version) and obtained the same results.

are you still trying to boot the CD installer?

as I mentioned above the installer does not boot on the Pismo for some reason

but the CD installer contains a hard drive image, if you manually deploy this hard drive image to the HDD of the pismo etc then replace its Mac OS ROM file with my patched version then it should boot up

 

[weckart]

was just reading back through this thread and noticed i missed the last 2 comments my bad! are you still trying to boot the CD installer?

He's not been logged into MR since last August. I suppose he must have given up.

 

[forzamyro]

I have deployed the hard drive img to the HDD of my pismo then replaced its Mac OS ROM file with your patched version.
But the screen powered off after the icon parade.
I have not given up.

 

[LightBulbFun]

I have deployed the hard drive img to the HDD of my pismo then replaced its Mac OS ROM file with your patched version.
But the screen powered off after the icon parade.
I have not given up.

that is strange, have you reset the PRAM and if you boot with extensions disabled see what happens?

what is your battery situation, are you plugged in via external power?

I have a battery in my pismo but its dead so I run from external power all the time

when you say the screen powers off, do you just mean the screen/LCD or do you mean the entire machine turns off?

 

[forzamyro]

I have reset the PRAM and PMU.
I run from external power all the time, and have tried with/without battery situations.

I tried again.
boot01-04 show the results of the normal boot.
shift01-04 show the ones of the boot with a shift key.


boot01: a warning of internal memory check


boot02: icon parade


boot03: just a moment


boot04: putt!


shift01: no extensions!


shift02: no icons


shift03: just a moment


shift04: putt!

The screen/LCD clicks out with a small sound like "putt!".
It seems that the entire machine turns off.

But there were some changes this time.
There appeared a warning of internal memory check.
(boot01 and also in a shift boot process)
And I noticed the "Backside L2 cache" disappeared in the System Profiler.

 

[LightBulbFun]

as a side note I wonder if there is a way to make Mac OS 8.6 boot with newer ToolBox ROM images, the latest for 8.6 is 2.5.1 IIRC which is rather limited in its hardware support

would be neat if we could use 10.2.1 or something!

Roll your own.......

tbxi

Tools to compile and inspect Macintosh ROM images

pypi.org

Usage:



Build:

I had a play with this but sadly could not really get anywhere (either a ROM that would not load or the same error as bellow, but I may still play with it tomorrow some more)

but I did notice that Mac OS 8.6 fails to boot on the 10.2.1 ROM not with a "this system disk is incompatible with this machine" error

but with just a crash error just as the Welcome to Mac OS screen comes up, which makes me wonder what the issue is exactly

(booting with extensions off made no difference)

 

[Macbookprodude]

Can this work on the Titanium 1Ghz ??

 

[Amethyst1]

I got 8.6 to boot on a 500mhz Ti.

 

[Macbookprodude]

OS 8.6 is dead.. lets make OS 9 GREAT AGAIN !