18 Apr
2013
18 Apr
'13
8:35 p.m.
On 04/18/2013 01:28 PM, Tony Duell wrote:
Under the removeable cover, in front of the carriage,
are 6 slots for the
font cartridges. The cartridges each cotnain a couple of EPROMs.
THe electroncs is based round a pair of Z8s (character input and
mechanism control) and a Z80 (comamnd procesing).
The Diablo dot-matrix that I used was in a 630-ish case, but the
carriage area cover was fully detachable, not hinged/cantilevered. I
don't recall if the power supply was separate, as in the Hitype I
printers. Interface was a 50-pin ribbon (twisted-pair spectra-strip,
actually), so I suspect Dataproducts parallel.
The "smarts" were definitely Rockwell PPS--I vividly remember the
oddball staggered two-rows of pins on each side of the package. I
recall the one of the engineers who had worked on the thing mentioned
that the whole affair used no interrupts--and a whole bunch of timed
program loops. Probably around 1977.
The thing was so loud that it was used only as a backup printer. We
used a modified Teletype 40 band printer--running tractor-feed
132-column green-bar paper. Heckuva rugged thing--it just ran and ran.
--Chuck