Recent content by speakers

  1. speakers

    Macintosh IIci strange power on behaivor

    Yep. In my case, a similar problem showed up after recapping and persisted after replacement of UE13. Removal of caps C10..C13 again, more cleaning with IPA and application of additional solder mask did the trick though. There's a collection of RC timer circuits sensitve to lingering cap juice...
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    PowerMac 7100 and Linux

    I've now confirmed that the nvrm resource of Mac OS Loader can be edited to change the initial value of 'real-base' and 'load-base' variables etc. And it is indeed necessary to update the checksum word (16-bit word offset 2) of the resource. I use DeRez on OSX to decompile the resource fork of...
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    PowerMac 7100 and Linux

    Thanks for this effort. It does seem to show that the Loader constructs nvram in memory from using a number of its resources. This is consistent with what I see in ResEdit for the Loader: This is taken from the install kit. I can edit 'auto-boot?' to false, re-install and have it take effect...
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    PowerMac 7100 and Linux

    I'm able to launch the BSD boot loader (ofwboot.xcf) from the floppy but I get in dreaded OFW claim failure since I'm unable to override the real-base and load-base variables as required. I'd really like to know where the disk-based OFW is stashing nvram so I could mess with it or at least set...
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    PowerMac 7100 and Linux

    Resuming after a vacation pause... I reverted my PM7100 to 24MB RAM (down from 136MB). After repairing the boot volume which was causing Copland to halt in the debugger, it then booted to Finder although it hangs there. I'm running the PowerPC debugger on my SE/30 with cable between modem...
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    PowerMac 7100 and Linux

    So I went back and installed a clean System 7.5. I had to grab a copy of the original 61/71/8100 installation CD from Macintosh Garden because none of the trusty Legacy Iso install images wanted to recognize my PM7100. Copland installed again but the capslock snag key again failed to give me...
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    PowerMac 7100 and Linux

    Thanks. Looking at release dates, 7.5.5 was Sept 96 whereas Copland D11E4 was June 96 .. so it may well matter.
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    PowerMac 7100 and Linux

    Yes and no. On my first install, it booted back into 7.5 and I used System Picker to select the OS8 system folder. That seems to screw things and leads to the F/7FFFF SadMac. At this point I could see that the boot blocks weren't the special Copland intercepts that point to the Mac OS8 Loader...
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    PowerMac 7100 and Linux

    And poking around the Copland D11E4 install kit, the previously attached ofw and nvram images are resources in the Mac OS Loader "app". And the modified boot blocks are another resource there.
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    PowerMac 7100 and Linux

    This is all fascinating and covered nowhere on the web. In fact, if you now google about it, you'll be sent this this very thread! I'm attaching a design doc from the Copland DDK v.0.4 about the I/O structure including Boot Services. Copland is indeed running OpenFirmware, but disk-based...
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    PowerMac 7100 and Linux

    I've tracked down the ram mis-configuration issue to a problem with BootX's PDM video re-mapping. BootX modifies the memory map passed to the kernel in a way that prevents correct discovery of simm banks. Without the nubus_simm bootarg, the kernel finds only 1MB off ram and panics. A patched...
  12. speakers

    68k->PPC->x86_64->arm64

    I've recently been tinkering with some 68k assembly code in a program originally developed for MacOS7. I'm using CodeWarrior Pro 4 under MacOS9 in a Qemu emulation of a PPC machine running on my M4 MacBook Air. Qemu is Intel. So what I have is: 68k instructions emulated as PPC by the 68k...
  13. speakers

    Macintosh IIci - no life even after recap

    Yes, 1 should be connected to 2.
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    Macintosh IIci - no life even after recap

    I think it should possible to put a shorting link in the base of the terminal block between pins 9 and 10 and still be able to put the PSU in place. But I haven't ever tried this .. I have an extender cable (made by cutting down an ATX extender).
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    PowerMac 7100 and Linux

    See https://github.com/speakers-k64/linux-2.4.27-pmac-nubus.git