Apple Network Server MacOS based ROMs found

[Mr. Macintosh]

This is wonderful news @trag !! I know @ClassicHasClass and I are standing by. Please let us know if here is any other way we could help

 

[joevt]

I used kansas_deinterleave to deinterleave all the ROMs. I think most people just want ANS 2.0.

This four chip arrangement is not flashable by Apple's flash utility which expects different chips.
Also, your ROM DIMMs won't have the write enable pin wired so we can't make our own flash utility?

 

[trag]

I used kansas_deinterleave to deinterleave all the ROMs. I think most people just want ANS 2.0.

ANS 2.0 means the first one above, "ANS Deinterleaved.zip"?

This four chip arrangement is not flashable by Apple's flash utility which expects different chips.
Also, your ROM DIMMs won't have the write enable pin wired so we can't make our own flash utility?

That is correct. Actually, I made a provision to enable the WE pin to all of the chips from the WE pin(s) on the DIMM. It's been 20 years since I laid the thing out. IIRC, connecting them requires installing a couple of 0 ohm resisters and maybe a wire jumper. But certainly, it would require your own programming utility, which follows the programming requirements for the HY29F800 from Hyundai or Hynix (same procedure for both). There's some theoretical discussion about programming in the large PEx thread I linked above.

My thought was to build an external programmer similar to Doug's mechanism for the Mac II family.

This is probably the first posting in that speculation: https://68kmla.org/bb/threads/pex-rom-project.23568/post-417941

And here is a later post laying out some of the solid options. Never got any further as far as building/testing hardware: https://68kmla.org/bb/threads/pex-rom-project.23568/post-418272

 

[joevt]

ANS 2.0 means the first one above, "ANS Deinterleaved.zip"?

Yes. That's the only one with 1 MiB files.

That is correct. Actually, I made a provision to enable the WP pin to all of the chips from the WP pin(s) on the DIMM. It's been 20 years since I laid the thing out. IIRC, connecting them requires installing a couple of 0 ohm resisters and maybe a wire jumper.

Any reason to not connect them?

But certainly, it would require your own programming utility, which follows the programming requirements for the HY29F800 from Hyundai or Hynix (same procedure for both). There's some theoretical discussion about programming in the large PEx thread I linked above.

Code for flashing various chips exists in New World Mac firmware updaters (Open Firmware code), and in open source utilities such as flashrom. I have a fork of flashrom for Mac OS X.

My thought was to build an external programmer similar to Doug's mechanism for the Mac II family.

This is probably the first posting in that speculation: https://68kmla.org/bb/threads/pex-rom-project.23568/post-417941

And here is a later post laying out some of the solid options. Never got any further as far as building/testing hardware: https://68kmla.org/bb/threads/pex-rom-project.23568/post-418272

I'll read those later. I was thinking, could the ROM DIMM have a switch to disable itself so that I can boot my Power Mac 8600 into its built-in version of Open Firmware, load firmware updating code from disk or serial port, then use the switch to enable the DIMM (bypass the built-in ROM), then run the firmware updating code? That way, I could use the Power Mac 8600 as a programmer for itself or other Macs. It would be useful for ANS since ANS doesn't have built-in ROM.

Apple flashing schematics were linked at
https://68kmla.org/bb/threads/mac-os-on-ans-modding-a-rom-dimm.51120/post-578579

Apple's flashing utility (for classic Mac OS) could be updated to add support for other chips. However, I don't think you can boot Mac OS, then disable the built-in ROM while Mac OS is running unless you disable interrupts and exceptions. So in this case, the ROM DIMM must already have a ROM that works with the Mac.

 

[trag]

Any reason to not connect them?

Enabling the use of WE was almost an after thought in the lay out. The _WE pins are all hard wired high. I think I left clear traces between _WE and Vss, but they would have to be physically cut and then the line to the DIMM _WE pins connected with resistors and I think in one case a jumper. It's doable but inelegant.

Also, any machine in which they're use would need to hold the _WE pins in the DIMM socket high or the ROM would not function. It seemed safer to just wire them high.

With more time to massage the layout I could have arranged resistors to tie _WE lightly high, so the status of the DIMM socket wouldn't matter, unless it dragged _WE low, but that wasn't my goal at the time and that could be problematical, if the DIMM sockets are tying those pins high in some way. Without knowing what Apple was doing with the DIMM socket WE pins in general, connecting them represented too many unknowns.

I don't remember what the status of Vpp is on the DIMM, but I don't think the chips I used need Vpp at all, being Flash, rather than EEPROM.

I'll read those later. I was thinking, could the ROM DIMM have a switch to disable itself so that I can boot my Power Mac 8600 into its built-in version of Open Firmware, load firmware updating code from disk or serial port, then use the switch to enable the DIMM (bypass the built-in ROM), then run the firmware updating code? That way, I could use the Power Mac 8600 as a programmer for itself or other Macs. It would be useful for ANS since ANS doesn't have built-in ROM.

A new module could be designed in that fashion. Just add some jumpers or DIP switch for the _CE pins to the chips and for the DIMM socket pin which disables the on-board ROM. If you're asking if there is a software way to do so, there are _CE pins on the DIMM module, but I'm not sure what they do on the DIMM socket, but there is no software method to control the pin that disables the on-board ROM. That would need to be a physical switch.

There's a pin in the DIMM module which leads back to the _CE pins of the on-board ROMs. Connect that DIMM module pin to Vss on the DIMM, and it supplies Vss into the DIMM socket, which connects back to the _CE pins of the on-board ROM, disabling them.

Apple flashing schematics were linked at
https://68kmla.org/bb/threads/mac-os-on-ans-modding-a-rom-dimm.51120/post-578579

Apple's flashing utility (for classic Mac OS) could be updated to add support for other chips. However, I don't think you can boot Mac OS, then disable the built-in ROM while Mac OS is running unless you disable interrupts and exceptions. So in this case, the ROM DIMM must already have a ROM that works with the Mac.

Apple almost certainly had some kind of stand alone flashing utility they could use. But once the modules were in development machines it was more convenient to not need to pull the module and replace it repeatedly.