Target Disk mode on unsupported MDD

[GaryN]

I had a discussion with someone on FB who says his FW800 MDD is no longer recognized in Target disk mode since he installed the unsupported OS9.
He says it will boot into TD mode but is not "seen" by any of 4 other machines he has: a G3, a Gigabit G4, a G5 and a 2012 MacBook Pro.
The FW seems to work fine otherwise and the MDD can "see" the other machines - it just "disappears" in target disk mode.

He is using a FW400-to-800 adapter plug but it doesn't seem to cause a problem if used between two of the other machines.

He wonders if something has been altered in ROM by the OS9 hack to cause this. The one thing unverified is whether the MDD was visible in TD mode before the OS9 install, but it's too late now without trying to "go back' and undo everything.

Can anyone with an unsupported post-mod FW800 MDD verify it is seen properly in TD mode please and,
does anybody know anything that could explain this or has he found a previously unrecognized issue with the OS9 install?

[IIO]

...what if you use the "regular" 400 port? (since no "changes" have been made for those at all)

[FdB]

Hey Gary,

If no one gets to this sooner, I’ve both varieties of MDD FW800 machines
(one without the unsupported OS9 installed… and one with) that I can
possibly test later on tonight / tomorrow. Seems to stand to reason (as
stated by IIO above) that perhaps the FW400 should-could-might work,
regardless. However, I’ll attempt both ways on both machines using the
FW800 to FW400 adapter cable AND a FW400 to FW400 cable.

My apologies, as I am more brain dead / pre-occupied than normal …
prepping for a freakin’ tax appeal and I’d much rather have my head
into the machines. It's nap time!

[GaryN]

...what if you use the "regular" 400 port? (since no "changes" have been made for those at all)

Same result on any/all.

…Seems to stand to reason (as stated by IIO above) that perhaps the FW400 should-could-might work, regardless.

This is one of those where it's difficult to get a precise reading of exactly what's going on - too many variables plus responses using "it" instead of specifying exactly which machine etc. so I have to keep asking over and over to be certain what's being said - but the question is: A FW800 MDD simply won't show up in target mode after the OS9 installation - period; true or false?

[FdB]

MDD with “unsupported OS 9” installed won’t even boot into target disk mode here.
Holding the T-key at startup results in the machine just shutting down.

Checked both FW400 ports for function and it wouldn’t even recognize VST 10GB
FW400 external drive at first. Hooked up the behemoth EZ-Quest FW400 external
and it mounted immediately. Rebuilt desktop & then it would mount the VST too.

Wondered about Open Firmware command to auto-enter Target Disk Mode on
restart and a quick search threw many flags concerning possible Open Firmware
password being enabled… explaining as “primary reason” why no target disk mode.
But, have yet to explore this any further.

Tested on MDD FW800 1.42GHz and both FW400 ports work with external
FW400 drives. Did not check the FW800 to FW400 cable use. (The MDD
would not recognize or mount a G4 laptop booted in Target Disk Mode.)
Only the bare OS is installed on this MDD. No apps and no OSX.

I’ll continue this on breaks this weekend (from my long columns of numbers).
Sorry not better news, yet.

[IIO]

This is one of those where it's difficult to get a precise reading of exactly what's going on - too many variables plus responses using "it" instead of specifying exactly which machine etc. so I have to keep asking over and over to be certain what's being said - but the question is: A FW800 MDD simply won't show up in target mode after the OS9 installation - period; true or false?

you didnt specify much either: are you sure you are using a sufficient OS? i.e. do you have the "universal" OS on the other machine, too?

when i didnt miss anything serious, it should normally work to boot over firewire between machines running the universal (or any other "same" OSes).
i just wonder how we can get this some day to work with minis and unsupported tibooks.

[macarone]

I have owned several MDD beginning shortly after the first model was released. These have always been a "problem" model from the beginning, needing various "mods" beginning with the fans, the power supply etc. From the first, switching from OS 9 to OS X even on models supporting OS 9 was a problem. For eg: holding the X key to boot into OS X never worked.

Firewire ports and Target mode were always flaky.

One thing that HAS always worked fine in both supported (FW 400 models) and unsupported models (FW 800) has been SATA PCI cards and IDE to SATA adaptors. No problems booting into OS 9 using SATA.

BUT: Target mode will work ONLY with hard drives connected to the IDE ports.

FireWire problems are often resolved by unplugging the power cord, holding the power button down for 5 secs, and replugging the power cord. Sometimes unplugging the power cord overnight if that doesn't work helps.

And different FireWire cases produce different results, also cases that worked often stop working even though the hard drive is fine, and will mount if removed and put into a different case/dock.

[GaryN]

I’ll continue this on breaks this weekend (from my long columns of numbers).
Sorry not better news, yet.

Thanks Fury. It's kinda looking like this is an issue that nobody's noticed before…

[DieHard]

I have owned several MDD beginning shortly after the first model was released...
Firewire ports and Target mode were always flaky.

Wow, never heard that one, let's clarify, FW Disk mode on an MDD 2003 FW400 Single or Dual will work 100% of the time, I literally used to do that to prep dozens of machines back in the day.  Now as for FW800 MDD, always loaded OSX via optical, so maybe an issue ?

BUT: Target mode will work ONLY with hard drives connected to the IDE ports.

Yes... kinda makes sense, you are turning the entire mac into an eternal FW have drive, so connecting other items to it, like other FW drives will not work in FW target mode; as far as internal SCSI drives, they use a card with it's own BIOS, so again will be invisible; items need to be connected to the logic board when turning you mac into an external Hard drive via FW target.  As a tech, this feature has "saved the day" too many times to count.

Seems like Metropahge may have alluded to this problem with the FW800 MDD back in 2016:
http://macos9lives.com/smforum/index.php/topic,3242.msg20625.html#msg20625

Lastly, since nanopico said:

Target disk mode doesn't rely on the OS, it's entirely in firmware.

The way to fix this issues on an MDD 800 may be to burn the FW400 firmware on a FW800 MDD, this is what many did BEFORE we made our famous boot disk for the FW800.  Somebody should PM a member with a FW800 unit running FW400 firmware and see if target mode works.  Also, if resetting the PRAM of a FW800 MDD that has not been modified and trying Target mode does NOT work, then that would make no sense since our modified ROM does not alter firmware at all, so a PRAM reset should put the unit back to "normal"

[GaryN]

The way to fix this issues on an MDD 800 may be to burn the FW400 firmware on a FW800 MDD, this is what many did BEFORE we made our famous boot disk for the FW800.  Somebody should PM a member with a FW800 unit running FW400 firmware and see if target mode works.  Also, if resetting the PRAM of a FW800 MDD that has not been modified and trying Target mode does NOT work, then that would make no sense since our modified ROM does not alter firmware at all, so a PRAM reset should put the unit back to "normal"

PRAM reset didn't do it. He did try the latest FW800-associated firmware update he could find (no, I don't know what ver.#)
I'll have him try the FW400. Any particular ver.# you prefer?

I just had a flash: Of all of the questions I asked, I didn't ask exactly where his boot disk was connected. So, does FW Target Mode just "find" the drive with the startup volume or does it have to be on the ATA 100 bus? Again, the MDD indicates it's in FW Target Mode - floating icon etc. - but nothing appears to the machine connected to it. Should the startup volume be able to be seen on either ATA bus?
I would test this myself but I can't get to my MDD at the moment…

[IIO]

then that would make no sense since our modified ROM does not alter firmware at all

yes, somehow not possible to dismiss ...

where his boot disk was connected. So, does FW Target Mode just "find" the drive with the startup volume or does it have to be on the ATA 100 bus?

...it works with optical drives, too, isnt it?

i have no clue but i would think that a computer in disk mode also knows about its currently chosen system folder (since that is stored in PRAM). and the other machine probably just asks her politely about this.

[GaryN]

i have no clue but i would think…

Not exactly the quality of an answer I was hoping for…

[IIO]

why, is it still to precise for you?

[FdB]

The way to fix this issues on an MDD 800 may be to burn the FW400 firmware
on a FW800 MDD, this is what many did BEFORE we made our famous boot disk
for the FW800.

Well, someone provide that FW400 Firmware, along with brief instructions on implementation.

I did install OS 10.4 and attempt TDM via the System Preferences - Startup Disk TDM choice.
Same results, it restarted and promptly shut itself down after a few seconds. Open Firmware
noted Boot ROM version as 4.6.0f1 and OS 9.2.2 Apple System Profiler noted: Mac OS ROM
10.2.1 (Generic).

It still mounts various FW drives using both FW800 and FW400 ports.
Off of the table now, or I'd check the FW version number currently installed.

I've spared details of many other sordid  tests from this weekend.

[GaryN]

I did install OS 10.4 and attempt TDM via the System Preferences - Startup Disk TDM choice.
Same results, it restarted and promptly shut itself down after a few seconds. Open Firmware
noted Boot ROM version as 4.6.0f1 and OS 9.2.2 Apple System Profiler noted: Mac OS ROM
10.2.1 (Generic).

It still mounts various FW drives using both FW800 and FW400 ports.
Off of the table now, or I'd check the FW version number currently installed.

I've spared details of many other sordid  tests from this weekend.

Thanks F.

[DieHard]

From Blitter back in 2014 on our forum:

Created an account here just to pop in and say that I have just solved this problem on my own retail MDD G4 FW800. My G4 now dual-boots between OS X Tiger and Mac OS 9.2.2, and both systems are recognized by the Startup Disk control panel. I had formatted its internal drive by using a surrogate iBook + USB enclosure and OS X Jaguar, allocating 1GB at the beginning of the drive for an OS 9 partition, leaving the rest for OS X. I also checked the "Install OS 9 drivers" box in Disk Utility so that the drive could be booted later on. I then installed OS X Tiger first as an escape hatch in case of OS 9 instability, though so far with the exception of a third-party SCSI card preventing it from booting, it has been running without any problems.

Essentially what locks native OS 9 support out of these machines, as has been suggested above, is that Open Firmware does not recognize "Mac OS ROM" as a valid tbxi file as of at least version 4.6.0, which is what the FW800 ships with. Since the FW800 and the earlier FW400 are so close in spec, I suspected that an earlier version of Open Firmware from the FW400 model would be close enough to at least boot the FW800 into OS X. Fortunately a firmware update is available from Apple for the FW400 models to fix a fan issue, bringing their firmware to version 4.4.8f2. However, Apple's firmware updaters refuse to flash the Boot ROM unless the current version is older than the desired upgrade. So, I worked around that by forcing an upgrade through Open Firmware itself. Here's how to do it on a FW800 with OS X already installed on a second partition:

- Download and install the 4.4.8f2 updater from https://www.macupdate.com/app/mac/10773/apple-g4-firmware-updater-x
- Open the bundle by right-clicking (or control-clicking) on the PMG4FirmwareUpdate.app file inside /Applications/Utilities and choosing "Show Package Contents."
- Navigate to Contents/Resources and drag the "Firmware" file to the root of your startup disk.
- Make note of the partition number of your startup disk-- this is important for the next steps. On a freshly-formatted drive with OS 9 drivers, the first visible partition is 9, which in my case meant my second visible partition with OS X installed was partition number 10.
- Reboot the Mac and hold down Command-Option-O-F to boot to Open Firmware.
- Enter the following two commands, substituting your partition number after the "hd:"
    load hd:10,Firmware
    go
- With luck, the white Open Firmware prompt will disappear and you'll soon see an OS 9-style progress bar at the bottom of the screen as the Boot ROM is being flashed.
- After the Mac automatically restarts, install OS 9 using the special version for the MDD FW400 (OS9General.dmg). The OS 9 System Folder should be visible and selectable using the Startup Disk preference pane.
- Enjoy.

I really believe that this should make a FW800 "act" like a FW400 and thus make Target FW mode operate "correctly"... but please do at your own risk.  These tricks may render some hardware useless and that is why the iMic modified ROM was so exciting.  Burning firmware was the "brute force" method of making unsupported G4s boot to OS 9, our more civilized methods do NOT mess with the hardware

FULL INFO HERE:
http://macos9lives.com/smforum/index.php?topic=762.75

[DieHard]

Was so long ago, that I forgot that snakecoils instructions were much better:

Success! :-) GREAT SUCCESS! :-)

I have found the way to start the firmware downgrade: I were right when I said a step was missing, I found the answer reading this page on Apple site

https://support.apple.com/kb/DL1175

If you look at point 3 of the article it say:

Press and hold in the Power button until you hear a long tone or see the Power button light flashing repeatedly. Release the Power button when you hear the tone or see the Power button light flashing. The update starts automatically.

And this is exactly what is needed to do: starting the Mac keeping pressed the power button! :-)

In brief here are the steps to follow:

1) Copy the Firmware file extracted in the way Blitter has said some posts ago, no matter about the OSX installed, a blank initialized partition is good. If the partition is the first in Disk Utility list its number should be 10

2) Shut off the Mac and be prepared to do the following steps as quick as possible

3) Press and keep pressed the front Power Button until it flashes, or until you hear a continuous tone

4) Release the Power Button and be prepared to press the key combination to enter Open Firmware (Cmd + Alt + O + F)

5) When you hear the Boing sound of reboot keep pressed the Open Firmware keys until the prompt comes out

6) At the prompt enter the following line

load hd:xx,Firmware

where, of course, the "xx" is the number of the partition where the "Firmware" file is

7) At the next prompt digit

go

The screen becomes black, the progress bar appear and the CD tray is ejected

9) When progress bar has reached the end the Mac reboots, the CD tray close and you have an OS9 bootable FW800 PowerMac :-)

The Info panel reports correctly 4.4.8f2 as firmware version and the OS9 boot is available as option in Startup Disk preference panel. I used the OS9General.dmg extracted from the Install disks of my other FW400 MDD.
OS9 boot went fine, I skipped the annoying registration screen pressing CMD + Q and everithing seems ok.
For who is interested in the FW800 port I can confirm it works well under OS9 but I don't know about its speed in this environment if someone has some disk benchmark tool to suggest I will be happy to do some test. In OSX 10.4 the speed is full 80 Mb/s, I have tested it with Xbench and obtained 76 Mb/s with an old 320 Gb Seagate Freeagent powered directly from Firewire 800 port.
I don't know anything about the Bluetooth and Airport Extreme functionality since I haven't these devices.
I will perform further tests in the days to come but until now I am really really happy! :-)

About the firmware upgrade back to 4.6.0f1 I don't know... I accepted the risk of downgrade because this FW800 machine was abandoned in my Mac stuff from long time but if the MDD is a tool of your job I can't reccomend to do this step until you are absolutely sure that none of the functionality is missed or altered.

If Blitter has performed this modification long time ago maybe he can share with us his experience. Here all seems to work very well! :-)

Enjoy!

[FdB]

Unsatisfied completely with previous repetitive TDM results of the 1.42 GHz MDD
FW800 here… a FW800 1GHz MDD is now on the table. Running OS 10.4 and
TDM-booting and being recognized by other G4s… und connected external
FW drives are all working a-ok. Same 4.6.0f1 Boot ROM version noted on
the 1GHZ. No OS 9 (unsupported) or otherwise (Classic ¿) present and
no expansion cards of any sort.

Will install unsupported OS 9 later and see if that might thwart it
from being recognized by “others” and/or booting into TDM with
the “unsupported” OS 9 install… in an effort to replicate Gary's
reported TDM "non-performance".

And then… (if TDM falters) may attempt Firmware downgrade from the
info graciously provided here by Herr DieHard - concerning Blitter &
snakecoils relative downgrade approaches (circa 2014).
Thanks DH.

[GaryN]

I really believe that this should make a FW800 "act" like a FW400 and thus make Target FW mode operate "correctly"... but please do at your own risk.  These tricks may render some hardware useless…

I have a feeling that this may be where the patient has an epiphany re: just how important it really is to him to have the damn thing able to enter TDM anyway.
Risk vs. reward…

I'll let you know what happens.

[Hyram]

One thing I recall about TDM and the MDD was that you only got whatever was connected to the ATA/100 (rear) connector available over FireWire TDM - whatever is on the optical bays connector, on the ATA/66 (front) connector or in a slot wouldn't be available. G4-books and the Mini, yes, you got the optical drive, but not the towers. At least, I never had anything not on the closest-to-the-CPU 40-pin appear over TDM.

Also, some PCI cards (eg poorly-coded SCSI host controllers - I'm looking at you, ACARD!) could play merry hell with TDM.