On 2009-04-30, Howard R Garner wrote:
[ ... ]
I also remember working witht he 8 inch floppies. Connected to my Heath
H-89 at the time
Did that one use hard sectored floppies or soft sectored?
In late 60's we had a MonroeRobot computer. From power off you had to
load everything from punch tape, then load our test data tape to get
results. Our data came from our test equipment via a FlexWriter with a
punch attached. Interesting time in the Navy.
That reminds me of one of the earliest of the interfacings that
I did. I did not have a terminal, just an ASCII keyboard, so I worked
on interfacing an 8-level punch Flexowriter as the output device. Lots
of nasty work translating ASCII to what that typewriter mechanism had as
characters, and dealing with the shift or unshift before print whenever
there was a change. The entire code to do that lived in a 256 byte
1702A EPROM, and the translation table from ASCII to the weird
characterset the Flexowriter used occupied a second 1702A. Needless to
say, the code was written in 6800 assembly language -- and then I had to
hand assemble it, because I didn't have enough RAM or an assembler and
editor that early in the game. :-)
Things went fine until the anodizing on the Oliver Audio optical
punched tape reader broke down, and the Flexowriter cranked 240 VAC into
the 680b. I did manage to get it working again -- but close to 100%
chip fatality on the CPU board and front panel -- though the RAM chips
on the 16K board (which cost more than the computer did) did survive,
with just a couple of bus drivers zapped there.
Yes -- BASIC came on a punched tape, and after a couple of
safety copies got worn to too soft, I finally nearly burnt out the punch
on the Flexowriter punching a copy onto Mylar tape. But I still have
that punched tape.
A bit later there was the audio cassette interface board, and
the BASIC plus an editor and assembler on the cassette tapes.
Enjoy,
DoN.
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