On Jan 7, 2026, at 12:47 PM, Richard via cctalk
<cctalk(a)classiccmp.org> wrote:
In article <ab1dea3f-947a-4813-8cad-b57057af2c7d(a)snowmoose.com> you write:
I inherited a C. Itoh CIT-220 with no keyboard.
Is the keyboard model-
or C. Itoh-specific or will other keyboards work with it?
By the time we get to the VT 220 and clones, it's likely that there's
a microcontroller inside the keyboard that is doing the communication
with the main unit. Typically the communication is 1200 baud serial
bit stream with unknown contents.
I would try an LK-201 keyboard, the keyboard used with the VT 220. I
am not aware of any service manual (or even a user manual!) for this
terminal.
The LK201 indeed has a microcontroller inside. It communicates via serial communication,
8 bit UART at 4800 baud, RS232 levels. The protocol is fully documented in the Pro 300
Technical Manual (on Bitsavers).
If the C.Itoh terminal uses that same interface, one option if you don't have or
don't want to use an LK201 is to use one of the two LK201 emulators I designed (one
for a PS-2 style keyboard, one for a USB keyboard). Both use small Arduino controllers;
the design is open (code, circuit, PCB) at
https://github.com/pkoning2/lk201emu .
paul