Elf99 - rebirth of a classic

From: Ethan Dicks <erd_at_infinet.com>
Date: Tue Nov 10 22:44:13 1998

> < > for a intersil 6100 (12 bit pdp-8) based system.
> <
> < Any schematics? ;-)
>
> Yep!

Do tell.
 
> Memory mapped IO on the 1802 was trivial to do and could be used to good
> advantage (1861 used it for the display).

That wasn't memory mapping. The 1861 DMA'ed the video data out.
 
> < Coincidentally, I purchased a PDP-8/L at 16 for the princely sum of $35
>
> Had an 8e years ago and gave it away, looking for another.

I saw one at the Computer Museum of America, but I don't think it is
available.
 
> < Still, the latch required +5.0VDC, the only part with a tight power
> < requirement.
>
> The latch was not fussy about power, the led portion was power hog.

Well... they _were_ nice and bright. Ah, the countless hours I spent
staring at those ember-bright dots, counting toggle pulses in my head
to fix a one-byte bug.

Ob1802Trivia - don't execute the one "missing" instruction, 0x68. ISTR
that the CPU went berserk and whomped memory randomly.
Received on Tue Nov 10 1998 - 22:44:13 GMT