Macintosh 512Ke: Difference between revisions
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| os = System 1.0 – System 6.0.8 | | os = System 1.0 – System 6.0.8 | ||
| predecessor = [[Macintosh 512K]] | | predecessor = [[Macintosh 512K]] | ||
| successor = [[ | | successor = [[Macintosh Plus]] | ||
| codename = M0001E | | codename = M0001E | ||
| model = M0001E | | model = M0001E | ||
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| '''Bus width''' || 16-bit data • 24-bit address (16 MB logical) | | '''Bus width''' || 16-bit data • 24-bit address (16 MB logical) | ||
|- | |- | ||
| '''ROM''' || | | '''ROM''' || '''128 KB “Plus-class”''' ROM | ||
*(Twice the 64 KB of the 512 K / 128 K; adds HFS, SCSI Manager, 800 K disk routines)* | *(Twice the 64 KB of the 512 K / 128 K; adds HFS, SCSI Manager, 800 K disk routines)* | ||
|- | |- | ||
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| '''Sound''' || 8-bit PWM DAC via VIA timers • 22 kHz RC filter → LM380 amp | | '''Sound''' || 8-bit PWM DAC via VIA timers • 22 kHz RC filter → LM380 amp | ||
|- | |- | ||
| '''Disk I/O''' || | | '''Disk I/O''' || '''Sony OA-D34V-22 800 KB''' auto-inject 3.5″ drive • IWM controller | ||
|- | |- | ||
| '''Ports''' || DE-9 mouse/KB • DB-19 ext. floppy • RS-422 serial × 2 (230 kbps) • 3.5 mm audio-out | | '''Ports''' || DE-9 mouse/KB • DB-19 ext. floppy • RS-422 serial × 2 (230 kbps) • 3.5 mm audio-out | ||
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! Range !! Size !! Purpose | ! Range !! Size !! Purpose | ||
|- | |- | ||
| $000000 – $07FFFF || 512 KB || | | $000000 – $07FFFF || 512 KB || '''DRAM''' (program, heap, frame-buffer) | ||
|- | |- | ||
| $400000 – $41FFFF || 128 KB || | | $400000 – $41FFFF || 128 KB || '''ROM''' (v3.4 “Plus” Toolbox) | ||
|- | |- | ||
| $480000 – $4BFFFF || 256 KB || | | $480000 – $4BFFFF || 256 KB || '''I/O''' (VIA 1/2, SCC, IWM, VBL PAL) | ||
|- | |- | ||
| $500000 – $5FFFFF || 1 MB || | | $500000 – $5FFFFF || 1 MB || '''Reserved / not decoded''' | ||
|- | |- | ||
| $600000 – $FFFFFF || Mirrors / ghost ranges | | $600000 – $FFFFFF || Mirrors / ghost ranges | ||
|} | |} | ||
*Frame-buffer note:* 22 016-byte display buffer lives at | *Frame-buffer note:* 22 016-byte display buffer lives at '''$07B000 – $07FFFF'''. | ||
=== ROM Layout (v3.4 128 KB set) === | === ROM Layout (v3.4 128 KB set) === | ||
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=== 800 KB Floppy Format === | === 800 KB Floppy Format === | ||
* 80 tracks • | * 80 tracks • '''double-sided''' • variable-speed GCR | ||
* 12 → 8 sectors/track (outer→inner) • 512-byte sectors | * 12 → 8 sectors/track (outer→inner) • 512-byte sectors | ||
* 800 KB formatted • still driven by IWM (no SWIM yet) with ROM-based speed tables | * 800 KB formatted • still driven by IWM (no SWIM yet) with ROM-based speed tables | ||
=== Key I/O ICs === | === Key I/O ICs === | ||
* | * '''6522 VIA × 2''' — timers, sound PWM, keyboard/mouse handshake | ||
* | * '''8530 SCC''' — dual RS-422 serial | ||
* | * '''IWM''' — Integrated Woz Machine floppy controller | ||
* | * '''MC6883 PAL''' — VBL interrupt & DRAM arbitration | ||
=== Sound Path === | === Sound Path === | ||
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=== ROM Enhancements vs. 512 K === | === ROM Enhancements vs. 512 K === | ||
* | * '''HFS file system''' support (400 KB disks can be HFS-formatted). | ||
* | * '''SCSI Manager''' present (unused until external SCSI upgrade boards). | ||
* | * '''“Backwards-compatible”''': still boots MFS and runs 128 K/512 K apps. | ||
=== Hardware Easter Egg === | === Hardware Easter Egg === | ||
Hold | Hold '''⌘ + Option + ⇧ + Clear''' at power-on for the hidden bass “startup” chime—retained from earlier ROMs. | ||
[[Category:Apple Vintage Computers]] | [[Category:Apple Vintage Computers]] | ||
{{Navbox-AppleVintage|state=collapsed}} | {{Navbox-AppleVintage|state=collapsed}} | ||