Recent content by michaelengel

Yes, all MIDI interfaces have the required clock generator. Check out this example schematic. The interface also is important since MIDI signals are not voltage driven but implemented using a current loop (to reduce problems with hum due to line noise coupling etc.), so the other function of the...

MIDI interfaces for Macs use an external 1 MHz clock divided by 32 to obtain the 31250 bps used, so you have to configure the SCC to accept an external clock. I completely forgot that I wrote something about this two years ago, maybe this old thread is useful...

This looks like some exception in time conversion functions, perhaps a division by zero due to the emulated CPU running too fast (but that's just speculation). As an alternative, you could try to run OS X 10.4 for PPC in qemu as described on github...

This seems to have worked now, thanks a lot for the support!

Thanks (also to Phipli)! Delivering to Germany seems to make it more difficult (surprise... though that should not happen in the EU). eBay tells me that "For tax reasons it is currently not possible to buy from this seller. We apologize for any inconvenience and recommend that you search for...

"This item does not deliver to Germany." :(

I'm not sure if the following bits are already known, both might be good sources of information about the protocol used by the Dynaport SCSILink and I didn't see these mentioned in the thread so far (great to see so many projects for classic Macs showing up here!). Joshua Stein has added...

I need to get an AIX machine running in order to test some things, maybe qemu will help (or my old Motorola MTX+ is still working after 20+ years). I'll try to find out more next weekend...

Unix software is often licensed based on the MAC address of (one of the) network adapters, which is a six byte value, so your machine ID 0026157F4c00 might just be a MAC address. You should be able to check using the following AIX shell command: netstat -v | egrep 'ETHER|Hard' In simple...

I would expect the code to be extremely dependent on code executing timing of the COP421 (software-timed loops etc. – didn't check the code). Nevertheless, a COP421 emulator on a fast modern microcontroller might be an option? (Edit) There's also a VHDL implementation of the COP400 at opencores.

Some assembler code to initialize the SCC for MIDI operation, which also uses an external clock (1 MHz to create the 31,250 bps baud rate used by MIDI), can be found in this MacTech article, see function "InitSCCChan". See the lines printed in bold that set WR11 of the SCC to use the external...

Although the original thread is already quite old, I think this information might still be useful. From the schematics (e.g. http://www.bitsavers.org/pdf/apple/mac/EarlyMacSchematics.pdf - note that this one uses the 9-pin D-Sub connectors) we can see that the external clock is provided on the...

Hm, strange, when I unpack the zip file again, I get the following (on OS X), so it seems the resource forks are intact. The file was generated using Finder on OS X 10.9, which is aware of resource forks as far as I know (in contrast to the zip/unzip command line tools). However, the FinderInfo...

Success! I found the tools on the January 92 ADC Developer CD in "Tools & Apps (Moof!)/Networking & Communications/AppleTalk Tools/" I knew it was a good idea to keep the old CDs around...

Are you aware of the fact that the ancient SUMACC cross-compiler tools from Stanford include a resource compiler called "rmaker"? The SUMACC code can be found in the 4.3BSD "new.tar.gz" fileset at http://www.tuhs.org/Archive/4BSD/Distributions/4.3BSD/ Building the cross-compiler itself on OS X...