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Home Forums 68kMLA Macintosh Portable Slot Hackage — #23
Post #23 by Trash80toHP_Mini
Source Forum68kMLA
Category68k
Post DateMon, 7 Oct 2013 - 17:55
Original URLhttps://68kmla.org/bb/threads/macintosh-portable-slot-hackage.28307/
Post
THX, unfortunately, that pinout remained unchanged, or so it would seem, but electrically that may not be the case, IIRC.

Interesting twist:

Not sure about it, the clock on board says 25.175MHZ(z?) so I'm wondering if this may be a multiplier of one of the 68000 signals that translates into the 2X clock rate increase for the 16MHz 68030?

The only other ICs on MicroMac board are the five:

GAL16V8B-15LJ - High Performance E2CMOS PLD Generic Array Logic

• HIGH PERFORMANCE E2CMOS® TECHNOLOGY

— 5 ns Maximum Propagation Delay

— Fmax = 166 MHz

— 4 ns Maximum from Clock Input to Data Output

— UltraMOS® Advanced CMOS Technology

If the above means these can be driven up to 166MHz could I then replace the 68030 with a 33Mhz part for 2x acceleration over the 16MHz 68000?

Is the 6688802 detected and automagicly enabled by its appearance on the CPU bus or is there driver support necessary?

WTHeck would be the function of an IC implemented on the empty pads on the MicroMac accelerator?

mp.ls