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Boot Pre-Firewire iMac G3 from USB Challenge.

Snial

Well-known member
Hi folks,

I'm late to the iMac G3/DV USB Booting party - having only this week discovered that it's possible! You can read about how I did it here: Tuesday at 10:09 AM

@CC_333 seems to think it should be possible with all New World iMacs. It would also be worth checking if it works with pre-FireWire New World iBooks (e.g. the iBook/300), ideally as far back as the iMac G3/233 Rev A. The earliest iMac I've used is a blue 266. So, does anyone have a working iMacs or iBooks from that era to test? (@GRudolf94 has a possibly fixable iMac G3/233).

I would start by trying to boot maybe Mac OS 8.6 or Mac OS 9.0.. 9.1, simply because I tend to feel more confident with OS's that need fewer resources (so someone with 64MB of RAM could boot 8.6 or 9.1), but there's a good argument for 9.2.2 as I understand that on New World Macs the last versions were less buggy (whereas on Old World Macs the latter versions became more flakey). I guess the bootability also depends on the Open Firmware revision.

Who has a suitable iMac they're willing to test?
 

joevt

Well-known member
What version of Open Firmware / BootROM does your iMac G3/DV USB have?

I think you need at least Open Firmware 3 4.1.9f1. I'm not sure about earlier versions except 1.1f4 in the B&W G3 cannot boot USB.

Search the ROM for usb-ms-class and firewire-disk-mode. I suppose you could just connect a disk and see if it appears in dev / ls under usb or firewire.

To make USB or FireWire bootable in older New World Macs or Old World Macs, you would need to port the USB or FireWire Open Firmware code from a newer Mac and put the code in a place where it can be loaded such as motherboard ROM, PCI option ROM, or a file on a disk, or blocks of an unused partition of a disk that is connected to a disk controller that has support preferably prior to probe-all.

Code:
Mac                                         OF version             ATY,Fcode versions       BAR max   Boot FW   Boot USB   Notes
                               
TNT Development A5c1                        Open Firmware, 0.992j                           128MB     No        No                         
7500,9500,8600,9600,Power Tower Pro, etc.   Open Firmware, 1.0.5                            128MB     No        No         256MB requires Mac OS 9 or Mac OS X nvramrc patches (see PowerSurge.of of joevt/XPostFacto for documentation of patches)
Power Mac 5400,6400                         Open Firmware, 2.0                              256MB     No        No         
Beige G3 Desktop                            Open Firmware, 2.0f1   1.49, 1.49               256MB     No        No         
Beige G3 Minitower                          Open Firmware, 2.0f1   1.49, 1.53               256MB     No        No         
PowerBook G3 Wallstreet                     Open Firmware, 2.0.1   1.54                     256MB     No        No         
PowerBook G3 Wallstreet PDQ                 Open Firmware, 2.0.1   1.54, 1.59               256MB     No        No         
Power Mac 4400 and 7220, Motorola StarMax   Open Firmware, 2.0.2   APL-1.0b33               256MB     No        No         
Power Mac 6500,TAM                          Open Firmware, 2.0.3   APL-1.0b33               256MB     No        No         
Power Express                               Open Firmware 2.0a9                             256MB     No        No         
Power Express                               Open Firmware 2.3                               256MB     No        No         
Beige G3 (v3)                               Open Firmware, 2.4     1.49, 1.53               256MB     No        No         
 
Power Mac G3 (Blue & White)                 OpenFirmware 3.1.1                              256MB     No        No         Apple PowerMac1,1  1.1f4   BootROM built on 04/09/99 at 13:57:32
Power Mac G4 (PCI Graphics) Yikes           OpenFirmware 3                                  256MB     ?         ?          Apple PowerMac1,2
 
Power Mac G4 Cube                           OpenFirmware 3                                  ?         ?         ?          Apple PowerMac5,1  3.2f1   BootROM built on 07/10/00 at 17:11:57
                              
iMac ?                                      OpenFirmware 3         1.69, 1.73, 1.77         256MB     Yes       Yes        Apple PowerMac2,1  4.1.9f1 BootROM built on 09/14/01 at 13:18:04
Power Mac G4 (AGP Graphics) Sawtooth        OpenFirmware 3         1.69, 1.73, 1.77         256MB     Yes       Yes        Apple PowerMac3,1  4.2.8f1 BootROM built on 10/11/01 at 14:12:47
Power Mac G4 (Gigabit Ethernet)             OpenFirmware 3                                  256MB     Yes       Yes        Apple PowerMac3,3  4.2.8f1 BootROM built on 10/11/01 at 14:12:47
Power Mac G4 (Digital Audio)                OpenFirmware 3                                  256MB     Yes       Yes        Apple PowerMac3,4  4.2.8f1 BootROM built on 10/11/01 at 14:12:47
Power Mac G4 (Quicksilver)                  OpenFirmware 3                                  256MB     ?         ?          Apple PowerMac3,5  4.2.3f1 BootROM built on 08/01/01 at 11:14:42
                                            OpenFirmware 3                                  256MB     ?         ?          Apple PowerMac3,5  4.2.5f1 BootROM built on 08/16/01 at 22:19:35
Power Mac G4 (Mirrored Drive Doors)         OpenFirmware 3         1.73, 1.77, 1.83, 1.86   256MB     Yes       Yes        Apple PowerMac3,6  4.4.8f2 BootROM built on 09/30/02 at 10:24:31
Power Mac G4 (FW 800)                       OpenFirmware 3                                  256MB     Yes       Yes        Apple PowerMac3,6  4.6.0f1 BootROM built on 02/20/03 at 13:52:27
 
Power Mac G5 1.6 (PCI)                      OpenFirmware 4                                  256MB     Yes       Yes        Apple PowerMac7,2  5.1.5f2 BootROM built on 09/21/04 at 11:58:53
Power Mac G5 1.8 (PCI-X)                    OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,2
Power Mac G5 2.0 DP (PCI-X)                 OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,2
Power Mac G5 1.8 DP (PCI-X)                 OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,2
iBook G4                                    OpenFirmware 3         1.94                     512MB     Yes       Yes        Apple PowerBook6,5 4.8.7f1 BootROM built on 09/23/04 at 16:13:38
Power Mac G5 ? (one of the following 3)     OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3  5.1.8f7 BootROM built on 10/26/04 at 16:30:32
Power Mac G5 1.8 DP (PCI)                   OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3
Power Mac G5 2.0 DP (PCI-X 2)               OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3
Power Mac G5 2.5 DP (PCI-X)                 OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3
PowerBook G4 15 inch Early 2005 A1106       OpenFirmware 3                                  ?         ?         ?          Apple PowerBook5,6 4.9.1f1 BootROM built on 01/21/05 at 10:51:16
Mac mini G4                                 OpenFirmware 3         1.95                     512MB     Yes       Yes        Apple PowerMac10,1 4.8.9f4 BootROM built on 03/23/05 at 14:22:23
PowerBook G4 DLSD                           OpenFirmware 3         1.95                     512MB     Yes       Yes        Apple PowerBook5,8 4.9.5f3 BootROM built on 09/22/05 at 16:17:32  ; allocates BARs by descending size when 512MB BAR exists
Power Mac G5 Quad                           OpenFirmware 4                                  512MB     Yes       Yes        Apple PowerMac11,2 5.2.7f1 BootROM built on 09/30/05 at 15:31:03  ; allocates BARs by descending size when 512MB BAR exists
PowerBook ?                                 OpenFirmware 3                                  ?         ?         ?          Apple PowerBook5,9 4.9.6f0 BootROM built on 10/05/05 at 16:45:50

BARs are allocated by ascending size except where noted.
Patches exist to support 512MB BARs on all Power Macs.
 

GRudolf94

Well-known member
Excuse the chaos - if it lives, it lives, and we can then proceed with testing.
 

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treellama

Well-known member
My pre-FW Clamshell (to my surprise, at the time) boots from a USB stick with 9.x on it. This is a relief as the CD-ROM barely functions so I have no other way to boot it without setting up a net boot server.

I have not been able to get it to boot Mac OS X from USB however.
 

Snial

Well-known member
What version of Open Firmware / BootROM does your iMac G3/DV USB have?

I think you need at least Open Firmware 3 4.1.9f1. I'm not sure about earlier versions except 1.1f4 in the B&W G3 cannot boot USB.

Search the ROM for usb-ms-class and firewire-disk-mode. I suppose you could just connect a disk and see if it appears in dev / ls under usb or firewire.

To make USB or FireWire bootable in older New World Macs or Old World Macs, you would need to port the USB or FireWire Open Firmware code from a newer Mac and put the code in a place where it can be loaded such as motherboard ROM, PCI option ROM, or a file on a disk, or blocks of an unused partition of a disk that is connected to a disk controller that has support preferably prior to probe-all.

Code:
Mac                                         OF version             ATY,Fcode versions       BAR max   Boot FW   Boot USB   Notes
                              
TNT Development A5c1                        Open Firmware, 0.992j                           128MB     No        No                        
7500,9500,8600,9600,Power Tower Pro, etc.   Open Firmware, 1.0.5                            128MB     No        No         256MB requires Mac OS 9 or Mac OS X nvramrc patches (see PowerSurge.of of joevt/XPostFacto for documentation of patches)
Power Mac 5400,6400                         Open Firmware, 2.0                              256MB     No        No        
Beige G3 Desktop                            Open Firmware, 2.0f1   1.49, 1.49               256MB     No        No        
Beige G3 Minitower                          Open Firmware, 2.0f1   1.49, 1.53               256MB     No        No        
PowerBook G3 Wallstreet                     Open Firmware, 2.0.1   1.54                     256MB     No        No        
PowerBook G3 Wallstreet PDQ                 Open Firmware, 2.0.1   1.54, 1.59               256MB     No        No        
Power Mac 4400 and 7220, Motorola StarMax   Open Firmware, 2.0.2   APL-1.0b33               256MB     No        No        
Power Mac 6500,TAM                          Open Firmware, 2.0.3   APL-1.0b33               256MB     No        No        
Power Express                               Open Firmware 2.0a9                             256MB     No        No        
Power Express                               Open Firmware 2.3                               256MB     No        No        
Beige G3 (v3)                               Open Firmware, 2.4     1.49, 1.53               256MB     No        No        
 
Power Mac G3 (Blue & White)                 OpenFirmware 3.1.1                              256MB     No        No         Apple PowerMac1,1  1.1f4   BootROM built on 04/09/99 at 13:57:32
Power Mac G4 (PCI Graphics) Yikes           OpenFirmware 3                                  256MB     ?         ?          Apple PowerMac1,2
 
Power Mac G4 Cube                           OpenFirmware 3                                  ?         ?         ?          Apple PowerMac5,1  3.2f1   BootROM built on 07/10/00 at 17:11:57
                             
iMac ?                                      OpenFirmware 3         1.69, 1.73, 1.77         256MB     Yes       Yes        Apple PowerMac2,1  4.1.9f1 BootROM built on 09/14/01 at 13:18:04
Power Mac G4 (AGP Graphics) Sawtooth        OpenFirmware 3         1.69, 1.73, 1.77         256MB     Yes       Yes        Apple PowerMac3,1  4.2.8f1 BootROM built on 10/11/01 at 14:12:47
Power Mac G4 (Gigabit Ethernet)             OpenFirmware 3                                  256MB     Yes       Yes        Apple PowerMac3,3  4.2.8f1 BootROM built on 10/11/01 at 14:12:47
Power Mac G4 (Digital Audio)                OpenFirmware 3                                  256MB     Yes       Yes        Apple PowerMac3,4  4.2.8f1 BootROM built on 10/11/01 at 14:12:47
Power Mac G4 (Quicksilver)                  OpenFirmware 3                                  256MB     ?         ?          Apple PowerMac3,5  4.2.3f1 BootROM built on 08/01/01 at 11:14:42
                                            OpenFirmware 3                                  256MB     ?         ?          Apple PowerMac3,5  4.2.5f1 BootROM built on 08/16/01 at 22:19:35
Power Mac G4 (Mirrored Drive Doors)         OpenFirmware 3         1.73, 1.77, 1.83, 1.86   256MB     Yes       Yes        Apple PowerMac3,6  4.4.8f2 BootROM built on 09/30/02 at 10:24:31
Power Mac G4 (FW 800)                       OpenFirmware 3                                  256MB     Yes       Yes        Apple PowerMac3,6  4.6.0f1 BootROM built on 02/20/03 at 13:52:27
 
Power Mac G5 1.6 (PCI)                      OpenFirmware 4                                  256MB     Yes       Yes        Apple PowerMac7,2  5.1.5f2 BootROM built on 09/21/04 at 11:58:53
Power Mac G5 1.8 (PCI-X)                    OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,2
Power Mac G5 2.0 DP (PCI-X)                 OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,2
Power Mac G5 1.8 DP (PCI-X)                 OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,2
iBook G4                                    OpenFirmware 3         1.94                     512MB     Yes       Yes        Apple PowerBook6,5 4.8.7f1 BootROM built on 09/23/04 at 16:13:38
Power Mac G5 ? (one of the following 3)     OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3  5.1.8f7 BootROM built on 10/26/04 at 16:30:32
Power Mac G5 1.8 DP (PCI)                   OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3
Power Mac G5 2.0 DP (PCI-X 2)               OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3
Power Mac G5 2.5 DP (PCI-X)                 OpenFirmware 4                                  ?         ?         ?          Apple PowerMac7,3
PowerBook G4 15 inch Early 2005 A1106       OpenFirmware 3                                  ?         ?         ?          Apple PowerBook5,6 4.9.1f1 BootROM built on 01/21/05 at 10:51:16
Mac mini G4                                 OpenFirmware 3         1.95                     512MB     Yes       Yes        Apple PowerMac10,1 4.8.9f4 BootROM built on 03/23/05 at 14:22:23
PowerBook G4 DLSD                           OpenFirmware 3         1.95                     512MB     Yes       Yes        Apple PowerBook5,8 4.9.5f3 BootROM built on 09/22/05 at 16:17:32  ; allocates BARs by descending size when 512MB BAR exists
Power Mac G5 Quad                           OpenFirmware 4                                  512MB     Yes       Yes        Apple PowerMac11,2 5.2.7f1 BootROM built on 09/30/05 at 15:31:03  ; allocates BARs by descending size when 512MB BAR exists
PowerBook ?                                 OpenFirmware 3                                  ?         ?         ?          Apple PowerBook5,9 4.9.6f0 BootROM built on 10/05/05 at 16:45:50

BARs are allocated by ascending size except where noted.
Patches exist to support 512MB BARs on all Power Macs.
OK, so when the iMac boots (and it's a winter 1999 iMac with a firmware upgrade), it says:

Apple PowerMac 2,1 4.1.9f1 BootROM built on 09/14/01 at 13:18:04.
 

joevt

Well-known member
OK, so when the iMac boots (and it's a winter 1999 iMac with a firmware upgrade), it says:

Apple PowerMac 2,1 4.1.9f1 BootROM built on 09/14/01 at 13:18:04.
That is one of the firmwares in my list that has USB and FireWire disk fcode.

Winter 1999 is iMac (266 MHz) from January 1999 which EveryMac says is iMac,1

EveryMac says PowerMac2,1 is October 1999 (Fall 1999 or Late 1999)
- G3/350 (Slot Loading - Blueberry)
- G3/400 DV (Slot Loading - Fruit)
- 400 DV SE (Slot Loading)

Which iMac do you have? Was the firmware iMac,1 and upgraded to PowerMac2,1?
 

Snial

Well-known member
That is one of the firmwares in my list that has USB and FireWire disk fcode.

Winter 1999 is iMac (266 MHz) from January 1999 which EveryMac says is iMac,1

EveryMac says PowerMac2,1 is October 1999 (Fall 1999 or Late 1999)
- G3/350 (Slot Loading - Blueberry)
- G3/400 DV (Slot Loading - Fruit)
- 400 DV SE (Slot Loading)

Which iMac do you have? Was the firmware iMac,1 and upgraded to PowerMac2,1?
Sorry, of course, there's two Winter 1999s, since Dec 1999 is also in Winter, which is when my sister's family bought the iMac G3 DV/400 (which I've acquired).
 
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