29 Jul
2000
29 Jul
'00
4:48 a.m.
On Fri, 28 Jul 2000, Sellam Ismail wrote:
I came across a deliciously mysterious computer today
in a local thrift
store.
. . .
It's a machine made by OKI of Japan (the same company apparently that made
the Okidata printer line). It's called the Small Computer Model 10 (as
indicated by the photo of the nameplate). At first I thought it was just
some dumb terminal until I started looking closer at it and discovered it
was indeed a computer.
There were a couple of OKI machines. I've run across disks from an Oki
BMC if800 model 20, and an Oki with MS stand-alone-BASIC (like those
NEC-DOS ones) I've also heard that they made an MSX machine.
The left-hand side features the power switch and two
momentary buttons,
one marked IPL and the other NMI.
IPL was IBMese for "Initial Program Load" IBM at one point didn't like
"bootstrap" nor "boot" due to its origins in Guy DuMaupassant's
(sp?)
Baron Von Munchausen stories (the baron was sinking into a swamp and
lifted himself out by his bootstraps)
[IBM also didn't like the word "motherboard" due to phrases from the 60s]
NMI is usually Non Maskable Interrupt. On the PC, that can be used for
loading a debugger into memory, and being able to force a jump to it by
shorting a pin.
I'd like to try to hook it up to a TV but I
don't know what pins I
should
use. I have a working scope but it's huge, old and is at my warehouse.
What would be a good way to try to determine which pins carry the signal?
find
ground; look for appropriate pins carrying signal resembling NTSC?
The right-hand side has three DIN connectors, labelled
L-PEN (lightpen),
TV (probably an RF connector), A-CMT (?). Finally, there is a DB-25
RS-232C connector.
How many pins in those DINs? RS used a 5 pin DIN for composite video on
the Model I, and IBM and RS used the same 5 pin DIN pinout for cassette
recorder, so there is a SLIM chance that they might have mimiced the RS
video DIN
--
Fred Cisin cisin(a)xenosoft.com
XenoSoft http://www.xenosoft.com
2210 Sixth St. (510) 644-9366
Berkeley, CA 94710-2219