[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: Chown ???

Mikkel L. Ellertson wrote:
Rick Stevens wrote:
Mikkel L. Ellertson wrote:
Jim wrote:
Rick Stevens wrote:
Patrick O'Callaghan wrote:
On Wed, 2009-04-08 at 15:27 +0000, g wrote:
Patrick O'Callaghan wrote:

'b-'. you did not answer which model and usage of paper. :)
asr33, paper scroll :-)
ASR33s also had the paper tape punch and reader.  KSR33s did not.  I
had both hooked up to my Altair 8800 back in '77 via 110 baud, 20mA
loop serial interfaces.

Ah, memories!
- Rick Stevens, Systems Engineer                      ricks nerd com -
- AIM/Skype: therps2        ICQ: 22643734            Yahoo: origrps2 -
-                                                                    -
-        Polygon: A dead parrot (With apologies to John Cleese)      -

ASR33 on  a Altair, that far back, You must be at least 100,  I started
out on a RCA 1802 8 bit and I still have it.
I modified it to work on S100 bus so I could get more memory , 64k , man
you were top dog with that kind of memory.

Maybe he was talking about an Altair 8008. Intel 8080 processor,
S-100 bus, front panel with status and data LEDs. Address/data
toggle switches, and a few control toggles.
No, an Altair 8800 (from MITS...Micro Instrumentation Telemetry
Systems).  IMSAI had the IMSAI 8080 (from IMS Associates, Inc.).  Bet
you didn't know the actual names of the companies, did ya?  :-)

I did at one time, but my memory isn't as good as it used to be. (At
one time, I could even toggle in the paper tape loader in binary
from memory.)

The Altair's front panel was set up with toggle switches in an octal
(3-switch gang) format on a metal front panel.  The IMSAI had   paddle-
style switches (a'la PDP-11s) in a hex (4-switch gang) format on a
Plexiglass front panel.  I had both machines, along with a Processor
Tech SOL-20 and a PolyMorphic Systems' Poly-88

The kit I had had SPST toggle switches for data/addresses. The lower
8 address switches were also used for entering 8 bit data. Things
like deposit/deposit next were SPDT center off spring-loaded
toggles. The If I remember right, the run/stop/step was
spring-loaded for step, but not for run. There were LEDs for data,
address, and status. The front panel was tied into the S-100
backplane. The CPU had its own S-100 card. The memory was another
S-100 card, and I/O was a third card.

They all had Intel 8080 or 8080A CPUs (well, the SOL-20 had an AMD
9080).  All were S-100 bus format.  The Altair had an 18-slot
motherboard (in separate 4-slot chunks you had to jumper together with
INDIVIDUAL wires), the IMSAI had a single, 22-slot motherboard.  The
Poly-88 had a single 6-slot motherboard, the SOL-20 had a 4-slot
expansion S-100 expansion bus (the CPU and all I/O were on the main
board, similar to what we have now).  All of them were kits (I melted a
HELL of a lot of solder back in those days).

Toggle in the paper tape loader in binary. Then load the system
monitor/program from paper tape. I remember loading an assembler
from paper tape, and then feeding the program source from another tape.
I had several different EPROM boards with primitive monitor programs
(think the old ODT program on DEC PDP-11s)

At that time, EPROMs and EPROM programmers were beyond my budget. It
was all I could do to afford the 4k memory card. (That changed

Yeah, and the 4k memory card cost close to a $100, I can remember when 2102 1k x1 memory chip cost a $1.00 each. I built myself a S100 8k memory board from scratch , (8 chips across and 8 rows down)with all gold plated ceramic chips , you could buy the blank S100 memory boards and populate them yourself. My last S100 memory board i built up was a 64k ram board, with low powered CMOS memory and I still have it. I need to find me a Computer Museum so I can donate some of the stuff I'm still carrying around.

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]