Recent content by joevt

Here's options for my fork of DingusPPC to allow the 1995-08 - 9630C68B - Power Mac 7200&7500&8500&9500 v2, SuperMac S900 ROM to detect bank sizes of 128 and 256 MiB for DIMMs that are 256 and 512 MiB. --comment "allow 512 MB DIMMs for 7200 v2 ROM" \ --patch FFF04538=54A4E054 \ --patch...

The algorithm for Hammerhead is different than for Platinum. Platinum Bank Base registers support addresses with this mask: 0x7FE00000 - 2 MiB resolution < 2 GIB. Hammerhead base address registers support addresses with this mask: 0x7FC00000 - 4 MiB resolution < 2 GiB. The algorithm for...

Maybe the hardware allows it. I don't think the ROM HWInit memory detection routines for Platinum might not. I've attached startup trace from DingusPPC. Ignore the sound DMA which is happening in another thread to play the boot chime while the RAM is being checked (the boot chime is played by a...

Here's the Platinum ERS.

On the DingusPPC Discord, you can find some memory controller documentation. Search for these: filename:Platinum_ERS_1.0.pdf filename:Hammerhead_ERS_Rev_1.1_19950925.pdf

A 128 MB DIMM is represented by two 64 MB banks in the Hammerhead and Platinum memory registers. In DingusPPC, 64 MB DIMMs and smaller are represented by a single bank but I suppose they could be represented by two banks also (i.e. two 32 MB banks for a 64 MB DIMM). The 7200 developer note...

Hardware developer notes at: https://leopard-adc.pepas.com/documentation/Hardware/hardware2.html#//apple_ref/doc/uid/TP40000979 Schematics here: https://www.macdat.net/repair/apple_schematics.html I guess they are not enough to answer your question? For the 7200 using Platinum memory...

I asked google "coil whine hot glue solution?" It says No, hot glue has a low melting temperature. Links to here for other solutions: https://www.techpowerup.com/forums/threads/how-to-quickly-easily-fix-coil-whine-coil-choke-noise.294015/...

The Apple Enet driver appears to have code that reads the PLSCCPort property so I guess the nvramrc script just needs to add this property. A system extension to add the property to the name registry might be more convenient (don't have to worry about nvram being zapped, etc). Just make sure it...

Right. ANS 2.0 ROM will use the AAPL,9500 identifier even if it detects itself to be an ANS machine. An ANS machine (whether using ANS ROM 1.1.20.1 or 1.1.22 or 2.0 or 2.26B6 or 2.26NT) will have PLSCCPort set to 1. A TNT machine will have PLSCCPort set to 7.

The PLSCCPort property is set by ANS 2.0 Open Firmware. It is not set by any other version of Open Firmware. 1 is for ANS 7 is for TNT I talked about this value at https://tinkerdifferent.com/threads/apple-network-server-macos-based-roms-found.4756/post-47393 If 1.1.20.1 is not writing the...

If the CD is bootable, then copying all of it to a hard disk partition should make the partition bootable. Then you boot that partition to do a real install to another partition. This only works if the software on the CD doesn't care that it is not booting from a CD.

There shouldn't be a difference. The point of the test is to prove it. If there was a problem, then it could indicate too much noice on the PCI bus, etc.

FireWire is nice because it's 40 MB/s, faster than USB 1.1 and SCSI 2. USB 2.0 doesn't work in classic Mac OS. A FireWire enclosure can be connected to modern macOS but for Tahoe, you need to use USB instead of FireWire. FireWire enclosures may include USB 3.0 but I think they are no longer...

Copy the Mac OS 8.1 installer to a small hard disk partition?