🇯🇵 NEC PC-8801 mkII SR: Part 2 (Keyboard 🤯) [TCE #0581]
32It's not uncommon to see PC-88 machines for sale sans keyboard, meaning that you then have to hunt down a keyboard that someone wants three times what you paid for the actual computer! The issue with the early machines is they used a large DIN ... 13-pin DIN according to this:
https://deskthority.net/wiki/NEC_PC-8801
So I found a relatively cheap keyboard for sale, with a large DIN. According to Deskthority, this should work.
However it has a 14-pin DIN plug ... huh? Such a thing exists? This must be for the original PC-8801!
So I'm back to the start. Maybe I can replace the cable - does it really need all 14 pins? Or design a keyboard myself from a schematic or reverse engineer this one, or just use someone else's design. Or continue hunting for a cheapish keyboard with a 13-pin ... not 14-pin ... DIN plug!
00:00 ... Intro
03:00 ... Motherboard clean-up started
04:48 ... Channel thanks & outro
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From Part 1:
Let's have a look at this NEC PC-8800/PC-88 series machine from 1985. Like the PC-8001 it is powered by a Z80 CPU . This particular version, the PC-8801 mkII SR Model 30, has twin 5¼" DD floppy disc drives built-in with 64KB of system RAM and 48KB of video RAM. I don't know if it works. It's designed for 100VAC.
It has an array of ports:
two 13-pin DIN keyboard sockets (front & left side)
DE9 I/O port (Atari joystick)
DA15 analogue RGB port
8-pin DIN digital RGB port
5-pin DIN B&W port
RCA jack for line-level audio output
DB25 serial port (RS232)
8-pin DIN for cassette (CMT, same as on PC-8001 & PC-8201)
printer port
volume control (an often overlooked but important improvement)
This machine also includes the optional Kanji card (KROM) that adds kanji support. Unless you get to see inside the machine it's not possible to tell if one is installed or not - simply taking the top case off is enough to see though.
Unfortunately this fellow has seen some weather in its time. The motherboard doesn't look too bad, with some bad corrosion limited to one small corner that I should hopefully be able to repair ... 74-type logic chips & passive components.
Apparently these often come without keyboards as they are highly prized for their blue ALPS key switches ... certainly mine didn't but I managed to score one for a decent price - important to ensure you get matching interface ... this machine has a 13-pin DIN, but this did change over the life of the machine:
https://deskthority.net/wiki/NEC_PC-8801
For the case I plan to get it professionally re-powder coated by a local company, similar to what I did for my Commodore PET and IBM PC/XT machines. The front fascia is plastic and should clean up with crème cleanser. I don't think Retr0brighting is required.
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Music by Karl Casey @ White Bat Audio
https://karlcasey.bandcamp.com/
/ @whitebataudio