< Not everyone has a Quest Elf. I, too, want to go beyond it, but for
< aesthetic reasons, I want to stay close to the original. My vision is
< a compromise between what we had in 1977 and what we would have wanted
< if we could have gotten it for the same price. When I built my Elf, I
< followed a friend's advice and installed a wire-wrap socket for the CPU
< He rolled his own I/O ports, with relay drivers and built a robot. I
< never did add anthing to mine, and quickly ran out of things to do with
Doing all that with a bas elf wasn't hard but very awkward.
It didn't latch the high address so 256bytes were it.
IO was what it was(switches and the Q led)
There was no easy expansion without corrupting the base design
so that some of the simplest programs did not run.
< I always wanted an Elf II, but couldn't afford the board. I wish now I
Same here but at teh time I was into S100 and just wanted to play with the
1802 a tiny bit and that was cheap.
< had saved for it. I got a 32k PET instead. Ah, well; choices. In any
< case, I liked the slots idea on the Elf II, but I don't recall too much
< materializing for it. The Elf II at the Computer Museum of America in
< San Diego has a plexiglass box over the boards and all the slots full.
< One was memory. I don't know about the other two. For that matter, the
Memory, Parrlel ports, serial ports, 1861 video board(may have been a
base level board option). The most highly developed elf was the one from
Netronics (ELF-II)
The VIP had a ram card, rom card, IO card and a sound effects card. Never
saw any of them. They were real easy to make.
My idea of a 1802 system was more like the 1802 Eval board rom RCA that
was unlike the elf series.
My 1802 wish list for the record.
Up to 32kram, 32k rom using standard pinouts so the 32k rom
can be EEpro, Eprom or flash. The 28 pin site can also accept
24 pin devices (6116, 2716, 2732...).
Minimum of one parallel out and one parallel in.
Elf style front pannel for programs with 6 hex leds (address and
data). data input would be toggle switches as they while not
cheap are easy to get and mount.
serial port, bit bashing serial IO gets tiresome and is limited
in speed.
VIP style cassette IO (tape storage)
proto area with holes enough to build a few IO things.
Bus brought to one connector (VIP compatable)
The reason for that is there are Tbasic, Pilot and other languages and
tools that all want more than 256 byts and Q-led.
If some one were to do it a "advanced 1861" in FPGA. the 1861
was a primitive device that did video DMA, With a little design effort
a similar device and be put in FPGA that would provide 256 horizontal
by 128 vertical using 4k of ram as a bit map. This enough to better
graphics and even display 32x16 characters using a 8x8 cell.
Going much further with 1802 is self limiting as it was slow and actually
a crude CPU. It was also like the PDP-8 in that it was blessedly simple.
Allison
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