🇬🇧 Husky Hunter: Part 2 (Temporary Keyboard Build Starts) [TCE #0495]
21As they keyboard membrane was knackered, I'm attempting to build a replacement keyboard so I can try the machine. For now I'm just using tactile switches on some prototyping board but as I've also drawn the schematic ... hopefully correctly ... in Kicad, I could also create a more professional-looking keyboard using proper key switches:
https://github.com/0ddjob/Husky_Computers
I was planning to just use the machine in another case but I get the feeling you would like it back in its original case ... so a replacement membrane will need to be designed and created eventually.
Let's see.
From Part 1:
Let's take a look at this marvel of British engineering from 1983, the ruggedised CP/M computer called the Husky Hunter by Husky Computers Ltd.
It comes with a massive 208KBytes of battery-backed RAM and runs a 4MHz Z80-compatible CPU, the NSC800. It uses CMOS extensively to allow it to draw a mere 10-20mA at 6V when idling. It includes some handy software in its 48KByte of ROM, including a CP/M 2.2 shell and BASIC.
Its sole means of communication is a DB25 port for V.24/RS232 serial communication.
This example of British computer engineering history was rescued from a garbage bin by Andy P. (ebay: synthpartsuk), so a big thanks to his eagle eyes.
Unfortunately it wasn't working (hence the toss I guess), so I had to dismantle it (which is what we do on this channel anyway).
Despite the big red label on the machine stating "DO NOT STORE WITHOUT BATTERIES", the usual corrosion-due-to-STORING-WITH-BATTERIES occurred - it also has an internal Varta rechargeable battery that, after 40 years, has also gone bad.
Despite the excellent design & build quality, they still made the mistake of using a delicate keyboard ribbon that crumbled after 40 years ... being near to the battery corrosion probably didn't help either.
So after a bit of cleaning, I supplied it with 6VDC to its battery terminal (negative to pin 16 of the keyboard connector) and then figured out the [ON] button pins on the keyboard connector: temporarily ground pin 17 to turn on ... i.e. pin 17 to pin 16.
And the machine booted with no issue! Looks great. The screen confirmed the ROM version: 9G60h. And the CP/M compatible O/S itself is called DEMOS.
Its days of being a ruggedised CP/M computer being thrown around in the wilds of the Scottish highlands or "run over by an Army truck" are well and truly over. I'm hoping to come up with a replacement keyboard and then re-house this fine fellow in an alternative case.
If you want to see more examples of the Husky computers, check out @TheEPROM9's channel - he has quite a few examples and videos on these machines - here's his playlist:
https://www.youtube.com/playlist?list=PL8611E27D2780084D
Lots of info here:
http://huskyhunter.shedlandrobotics.co.uk
Music by Karl Casey @ White Bat Audio (@WhiteBatAudio)
Song: Crawling
https://karlcasey.bandcamp.com/track/crawling