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22 Feb, 73 tweets, 19 min read
So the latest LGR Blerbs episode is on the Keypatch AT, an interesting mid-80s device to add functionality to early PC keyboards. I was thinking I had another model of Keypatch and I thought I should go pull it out of storage...

It turns out, NOPE! What I have is a CXI Keyboard MATE, which is clearly a similar device, but not a Keypatch.
Keyboard MATE. I don't know why all of "MATE" is in uppercase. It's got the same set of scroll lock/num lock/caps lock indicators like the keypatch
But instead of just adding on keys that are missing on early PC keyboards, it's got a whole set of different buttons, like PF1-PF24, which have up to three labels per key!
Like PF13 is PF13 on top, Red on the side, Source on the label above?
The PF keys include a lot of clearly specialized things which sound vaguely video related. foregrounds, backgrounds, fast forward...
Then it has this little separate 2x4 block with completely inexplicable buttons.
ChgSc (Change source?) Pr Control (Public relations control, clearly), PA1 and PA2 (Jump (which Kris Kross will make you)), WS Control, Finish, and... resize?
I was hoping there'd be more info on the bottom, like a little sticker giving a model number and a company and a date, but nope! there's just some double-sided adhesive pads, and a little switch thing
The little switch thing is completely unmarked.
Given that it's a 5-pin keyboard, I bet this is for selecting PC/XT or AT protocol.
And it uses the same 5-pin DIN passthru as the Keypatch AT.
So when I opened it up, "XT Rev. B." fell out.
So maybe this is XT only?
So when I opened it up, there's a label for Alphanetics Inc.
Why's that matter?
Because one of the only results for Alphanetics is a page that says they made a PCB for Genest. Genest being the company that made the Keyswitch AT!
So it's powered by an NEC D8749HC.
That's an 8-bit microcontroller, and for once it's not an 8051!

... It's an Intel MCS-48 compatible, the direct predecessor to the 8051!
It's also got two 7407s, which are hex buffers, for converting between MOS and TTL voltages.
It's got the same 1980s rectangular LEDs as the Keyswitch AT
And the obligatory key mechanism shot.
The look to be cherry compatible...
And they are!
There's no PCB labels for that dip switch.
The PCB says it's a 2-310-009 GRI. Doesn't seem to be any relevant results on google
It's also got a handwritten "S/N 417" (that's a small run!)
and a date: 6-11-87
So, it turns out these devices are designed to work with other add-ons:
The CXI PCOX/3270 PC Coaxial and PCOX/3270 PC REMOTE connections, to let you emulate an IBM 3270 on a PC.
The CXI Mate adds the extra function keys those terminals would have!
Those add-ons were to let PC compatibles work as 3278/3279 terminals, so you could connect to IBM mainframes like the IBM 3033.
CXI was apparently in Mountain View, about 2 miles from where I got these keyboard-add ons.

So it's possible these never sold, and are just left over hardware some employee took home
These last couple pictures come from Bitsavers:
So given that the PCBs have the Alphanetics name on them and Genest worked with them, here's my guess at what happened:
CXI worked with Genest to build the Keyboard MATE, as Genest was already doing a similar thing with their Keyswitches.
err, keypatch. I keep calling them keyswitches.
Here's the other thing I wanted to talk about.
So here's the ad for the Keypatch-10 from March 1986, Byte Magazine.…
So, the prices. You could get it for PC/XT, AT, and "compatibles".
Most compatibles would use XT or AT protocol so I don't know what that's about, but I guess some of the weird compatibles didn't.
So, as LGR put in the captions, those prices adjusted for inflation are:
204.24$ for the PC/XT version
223.47$ for the AT version
216.26$ for the Compatibles versions
But the real question I had watching the video is:
what does that compare to buying a new keyboard, at the time?
because thinking about it today, if you had a keyboard that didn't have some keys, why wouldn't you just buy a new keyboard?
you can get decent mechanical keyboards for those kinds of prices.
so let's look around the rest of the same issue of Byte and figure out what contemporary keyboards would cost, especially ones that add the AT keys that XT keyboards wouldn't have.
The first one we're gonna find is this Silicon Specialties store.
They only have one keyboard for sale, and it's a Keytronics 5151, for 159$. that's 382$ today.
that's a slightly weird-ass keyboard which has some fun layout quirks, but it it does have separate home/end/insert/delete/page up/down and arrow keys.
But yeah, that's 159$ for a new Keytronic 5151 vs ~90$ for a Keypatch-10.
For 99$ (238$ today) you can get a Key Solutions KS 8300. That's about the same price and doesn't have the keys the Keypatch gives you.
Another amusing thing I found on the way:
The Double Barrel hard drive/tape drive combo!
So you can easily back up your hard drive!

There's also the Alpha Micro Videotrax, which is another backup solution (like the Danmere Backer and ArVid) which back up onto VHS tapes.
Key Tronic was pushing the KB5151 pretty hard. They even offered a 25$ rebate if you mailed in your old PC/XT/AT keyboard.
Hey look, another VHS backup system !
This one is apparently called Hard Disk Intelligent VCR Backup, from TLM Systems
Here's some keyboards from Pine Computer:
They've got a "PC/XT look alike", 78$ (187$ today)
A selectric-II look alike, same price, an advance 100 key model 5151 (sounds like the Key Tronic one!), 109$ (262$ today),
and an AT-like keyboard, 98$ (235$ today)
Here's a set of interesting accessibility keyboards: The Light Talker.
You use an optical wand to select keys
And the Touch Talker, with a keyguard to make it harder to miss keys and require more pressure to activate them
Microsoft "Windows"? It'll never catch on. Stick to MS-DOS and BASIC interpreters, guys.
This ad hasn't gotten the memo that "Keyboard" is one word.
But they've got another 5151 for 79$ (190$ today)
and a 5050 for 59$ (142$ today)
Here's a no-name PC/XT style keyboard for 89$ (214$)
Here's something that hasn't aged all that well:
a PSA from OJ Simpson about how the Boys Club kept him out of trouble
Another generic PC/XT-style keyboard, 89$ (214$ today)
D&D Discount Counters (not that D&D) just has the 5151 keyboard, for 99$ (238$ today)
Suntronics, meanwhile, has a "Full Function Enhanced Keyboard" for 75$ (180$ today), and an AT-style keyboard for 110$ (264$ today)
Fortron Corporation has THREE entire keyboard for sale!
A 79$ 5150, a 99$ 5151, and a 109$ PC/AT keyboard.
Those prices today are 190$, 238$, and 262$
Budget Computers has two cheap keyboards:
A 5150-style for 56$ (135$ today), and an AT for 77$ (185$)
This is interesting: Corvatek is selling the "Key-Up interface" to let you use an IBM style Keyboard on any computer.
I think maybe they mean like CP/M machines and Apple IIs?
They also can sell 5150 and 5151 keyboards, for 112$ and 164$ (269$ and 394$ today)
The Diversified Group sells three keyboards:
a 5150 standard for 170$, a 5151 Deluxe for 180$, and a 5153 Touch Pad (!) for 290$
Today those prices would be 409$, 433$, and 697$ !
I found one of those Key tronic 5153s on ebay: That touchpad? it's not a pointing device. Instead it's like a macro pad!
Lots of great MS-DOS macros here
And we can all use this one in 2021
There's a couple other ones on ebay and they all have different buttons here, so clearly the macro set is swappable
anyway I bought one which includes software and manual so I'll be tweetin' about that in a week or two
JDR Microdevices is selling two keyboards.
The 80$ DKM-2000 and OH LOOK IT'S THE KB-5151 AGAIN, this time for 100$
(192$ and 240$ today)
Anyway those were all in the March 1986 BYTE Magazine:…
So that answers my question about how much this Keypatch thing cost in relation to a new keyboard:
About the same! It's a bit more expensive than a cheap XT-style, a bit cheaper than an AT-style one, but in general it's right in he same range of prices.
also in 1986 keyboards were rarely sold separately, if this magazine is anything to go with. This is, what, 20 ads for keyboards? There's computers sold including keyboards every 3 pages, and this magazine had 480 pages.
So in 1986 it seems like you'd tend to get your keyboard with your computer, and keyboards were mainly sold for people doing the comparatively rare build-your-own computers.
also, keyboards were really really expensive. like a lot.
All keyboards were going for prices that only high-end mechanical keyboards go for today, and more.
These days you can get a non-mechanical wired keyboard for 14$
You want it wireless? that's 19$
You want it mechanical, with RGB LEDs? 30$
Wireless mechanical? 50$
That's equivalent to 21$ back in Match '86.
But yeah. keyboards were expensive. The Keypatch may seem expensive but it was really just in line with other keyboards, so it'd actually be cheaper than doing a full upgrade to a new AT keyboard, by a good 20-30$ (which was a lot back then)
ANYWAY I don't have an XT computer + keyboard set up at the moment to plug my Keyboard MATE into, but when I do, I'll try it out and document what scancodes it is sending.

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