Hi folks.
This topic was posted almost identically on 'Deskthority', a forum on which I have read silently for a few years.
Same goes for this place here, which has a slightly different spirit, but of course shares the same kind of madness.
All this might be an indicator for my slightly geekish tendencies, especially when it comes to HIDs, but also in other fields - maybe driving a sluggishly restored Delorean DMC12 as a semi daily driver might also count.
Speaking of sluggish restorations: today I have a valid reason for my first post.
On Sunday, I got an ancient looking laptop for a song, which was non functional and had a completely dissolved NiCd-Battery which hat leaked all over the lower casing. The unit turned on, but was instantly emanating the dusgusting smell of burning electrolytes, and the screen was completly blurry and dark.
Although this little thing - a Bondwell B200 with german ISO keyboard - was a very cheap device at its time in the late 80s, built with an 80C88 processor that was outdated even in 1989 and made from extremely flimsy plastic that is so brittle after a few decades that it literally disintegrates under your hands if you touch it roughly, there is something about the keyboard that is quite noteworthy: it is clicky and feels simply fantastic.
It is by far the best keyboard I have ever touched, at least to my taste, and compared to white complicated Alps and normal Cherry MX blues. The switches are Cherry MX dark blue, except for the return and space keys, which are amber Omron switches.
Today, I cleaned the case and disassembled the little sucker. Inside I found the usual capacitor mess, so the soldering began.
After a thorough capacitor change and the a hasty reassemly, it started up flawlessly and asked for a boot disk, which I created using an old 486 hooked up via shugart bus to a TEAC floppy from my good old Amiga 500. It took 3 hours and was horrible, but finally worked.
I found out via another forum that the keyboard itself would be very hard to mate with a Teensy or any other microcontroller based solution due to its weird matrix, so I did not even try anything like this.
While many guys here might have voted for harvesting the switches, I decided to go down a different path that some of you might appreciate. However, I had the impression that many members here are more switch oriented, while the Deskthority are more into keeping vintage devices in their original state. Please correct me if I had a wrong impression.
Anyways, I set up a Raspberry Pi Zero W with Raspbian lite, installed TCPser and a few text based browsers (Lynx etc.) and a telnet daemon. Then I added an adapter from USB to RS232 and a nullmodem cable.
After rebuilding the Bondwell's battery pack, which consisted of six 'C' cells in a row, I was able to get the 5 volts for the Raspberry from it with little effort, and as one of the 2 720K floppy drives was not working anyway, I decided to put all this stuff inside the case instead of the right side FDD.
After adding a small footprint terminal program (CONEX) to the boot disk via Laplink (the old 486 was already back in the basement) and adding it to Autoexec.bat, the unit now directly boots into the terminal and logs on to the PI via Telnet. Interestingly, transmission works flawlessly up to 115200 baud, which is not common for a XT system .
The result is the best Linux terminal I ever had, fast enough for most command line stuff, including quick google searches and controlling my home automation if I was so inclined. Even mail, taking notes and reading news sites works quite well.
It runs for about 3 hours on 6 eneloop 'C' cells, with activated wLAN and bluetooth on the pi side.
The only remaining thing to do is to route a flat ribbon cable with a soldered DB25-connector to the inside in order to get rid of the big ass serial cable on the back.
Google goes 80s
Dark blue beauty
Ugly little things
Capacitor incontinence
Geekhack goes back in time