03.005 I recently bought an "M-c-T SpeeDemon" board. It's dated 1984 and draws a small apple on the screen after power-up. What kind of cache RAM does it have? There's a place for jumpers near the top of the card. Is there a way to control this thing through software or hardware?
Description
This article is from the Apple II Csa2 FAQ, by Jeff Hurlburt with numerous contributions by others.
03.005 I recently bought an "M-c-T SpeeDemon" board. It's dated 1984 and draws a small apple on the screen after power-up. What kind of cache RAM does it have? There's a place for jumpers near the top of the card. Is there a way to control this thing through software or hardware?
Your card may be a slightly later model. (I've never noticed ours draw a
hires apple on the screen-- darn it!) Possibly, McT came out with a revision
aimed at 128K IIe's.
The RAMs on our vintage model SpeeDemon are 100ns 2048x8 9128's (for a
total 8K of pretty speedy cache).
I once asked McT about the jumper block you mention, they said the jumper
is set at the factory to adjust on-card timing and to Leave It Alone. (On our
card, the jumper block has 5 pairs. The pair 2nd from the top is jumpered.)
There is also a jumper pair near the bottom middle of the card. This is
the Speed Jumper. Jumper it if you want 'demon to slow down for I/O accesses to
Slots 4 & 5. (The 'demon always slows for Slot 6 I/O ($C0E0 - $C0EF.)
According to the "Manual" (a folded card), pressing PDL-1 (Closed-Apple
on a IIe) upon power-up will engage a self-test. Pressing ESC at power-up will
turn OFF the card and allow running at normal speed. To turn OFF the card later
on, do a POKE (49152+256*S) where S= Slot # of the slot the card is in; then,
press RESET.
You can put the 'demon into any Slot; but, if you put it in Slot 0 (Slot 3
in a IIe), the card will not respond to any KB shut-off commands.
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