Jump to content

blitter

6502
  • Content Count

    95
  • Joined

  • Last visited

Recent Profile Visitors

549 profile views
  1. You assume incorrectly. The early Macs' video signal is designed for its analog board and nothing else. The closest analogue (pun unintended) to something contemporary with the Mac-- remember that VGA wasn't invented until 1987-- is the 350-line mode of EGA... and even EGA wasn't invented until *after* the first Macs shipped in 1984. The early compact Macs output 370 lines of video at a horizontal scan rate of 22.254kHz, of which 342 lines are visible. EGA tops out around 21.8kHz in 350-line mode which is *almost* what the Mac puts out. But don't misunderstand-- EGA and the compact Mac video s
  2. Neither SimCity 2000 nor Prince of Persia use QuickTime for music playback. Both of those games (as well as a number of others, such as SimAnt, Lemmings, Wolfenstein 3D,...) license the SoundMusicSys engine from Halestorm, which only generates software-synthesized sounds through the Mac's built-in audio facilities.
  3. I do know that the Sound Driver implementation in Mini vMac is buggy / incomplete-- Lode Runner running in AMS for example more accurately reproduces what a real Mac sounds like, whereas in Mini vMac some sounds are incorrect.
  4. Of course it modifies the VBLQueue directly-- it would be a dead giveaway seeing a call to _VInstall. You thought they'd make this easy?
  5. MacsBug doesn't live in the system heap. It lives in high memory above (BufPtr). The address stored at location $120 in low memory (if not null) points to where a debugger is installed. I would check to make sure there isn't a VBL task installed somewhere. I'm reverse engineering a different app that installs a VBL task that checks every other tick to make sure the replacement vectors haven't been tampered with. Such a thing could interrupt ordinary Toolbox calls, causing problems.
  6. 3.5" floppies? If they're not copy-protected, then Disk Copy 4.2 on the Mac should image them just fine. Extracting the data from them is another matter, but emulators such as LisaEm exist that might help there.
  7. Is there a particular reason why you don't want to use the patched HD SC Setup utility? I'm just curious.
  8. For folks in the Bay Area, I was at WeirdStuff Warehouse this past Sunday and near the entrance of the store, on a shelf they had four new-in-opened-box Miracle MT209A 9" monochrome SVGA CRTs for sale. $50 each. I picked one up for myself but they might still have some left, if you're interested in taking on a similar project to the OP...
  9. It's also possible that the connection from the speaker itself to the logic board might be faulty. My dad had a IIsi with an oxidized speaker connection-- this is a common problem with that model. If a sharp rap to the top of the case will occasionally restore sound, that might be the issue.
  10. I picked up a 23" Cinema HD they had when I visited there this past Saturday. All those Power Macs, ImageWriters, and the Personal LW were still there. The towers are missing bezels, as BMOW's photo shows.
  11. I traced the pinout of my GM ROM today just to confirm some of the conjecture in this thread, and raise a couple more questions: https://pastebin.com/nzxFhpXg - Pins 1-2 of the ROM socket indeed are wired to Vpp on all of the GM Flash chips. - /WE is not only present on the GM edge, but it's properly wired to all Flash chips. Whether /WE is configured on the Pippin itself for in-system programming, I don't know. - There are 16 8-bit Flash chips on the GM board instead of the four 16-bit PSOP chips on the retail board. Each Flash chip has 18 address lines vs. the retail board's PSOP chips
  12. Pseud040? http://headgap.com/~michael_connolly/
  13. I think top/bottom only matters with regards to writing, specifically a small bootstrap program, and since the Pippin ROM isn't organized that way then it's pretty irrelevant for our purposes.
  14. Looks like your pinout of what I assume is the ROM *socket* on the Pippin motherboard matches pin-for-pin my tracing of the retail 1.2 Pippin ROM board, defor (plus filling in a few missing pins in mine, namely the Write Enable, +12V, and /ROM). Thanks for sharing, this is very reassuring. EDIT: Scratch what I said-- of course it's the socket, but it's also the PCB, since it fits in the socket. That's what I get for posting at 230am...
×
×
  • Create New...