Firstly, a little guessing game - from what popular computer is this printed circuit board. Then, the keyboard barely works, so I fix it using just water and some abrasive cleaning techniques. Then I write a two line program in BASIC. 30 minutes of 8-bit joy 🙂
By Julian
Youtuber, shed dweller, solar charge controller aficionado
Its an early VIC with the onboard 5 volt regulator, I'd recognize that big black heatsink anywhere
I knew what that was the minute I set eyes on it, having repaired many hundreds of c= machines in the 1980s. You have one of the good ones, there, with the 2-pin power supply. Later ones used a 7-pin DIN connector and the supply was potted in epoxy, a frequent failure item. We used to sell aftermarket supplies for those machines, too. Skin oils on those keyboard contacts is NOT a good thing! Also, there is NO protection for the 6522 chips so you probably don't want to be running your fingers across the edge connectors at the back of the machine, or the joystick port. We also used to push a bit of black foam into joystick ports, which would save them from being zapped from static discharge, after replacing a bad chip in each case. Another thing that I liked about the VIC was that the edge connector was the more or less standard 44-pin size, so you could build stuff on boards with the appropriate edge fingers, and plug it right in. I wouldn't mind having one of those… 🙂
Edit: It's a little misleading to say you can only address 64KiB of ram with a 16bit address; because it's not true.
A 16bit address limits you to 65535(sorry, 65536, since 0 is also an address) unique addresses but does NOT in any way limit you to 64KiB of addressable memory. Connecting multiple SRAM IC address lines together, you can address an arbitrary number of chips giving much larger system WORD's per address effectively giving much more than 64KiB of memory.
The real limitation to memory is your bus width:
You can create 128bit system WORD's using only 16bit addresses, but if your bus width is only 8bits wide, that would limit you to transferring 8bits per clock cycle effectively slowing down your processor due to bus width.
Judging by the MOS chips even 15 seconds in my guess was some version of a commodore XD
The SID chip arrangement also gave it away XD
Knew it was a vic-20 from the moment I saw the processor.
Hãy mài mòn phần cao su dẫn điện màu đen để sửa phím không bấm được.
No IPA…
…Hell's teeth
I guessed that it was a commodore vic 20 just from the MOS chips and the type of datasette ports used.
Certainly not CBM's best bit of work, but that Omega Race cart was the best home version of the game until MAME came along.
Thought that looked familiar I think I have one of those in my back room some place. I recall the first one I got to play with, one of the patrolmen who worked for me had one, and he showed it off to me, I thought it was one of the greatest invetions Ihad ever seen, this was back in 1983 or 84 if memory serves. The next fellow I hired had a C=64 and it was so ver much nicer, abut two years later, I picked my first machine, that being a C=128 with 1571 disk drive, now that was computing, even got a monitor after tiring of looking at an old huge 19 inch color tv that nearly made my eyes bleed when playing games on the machine. That had to be 1985 as I had just changed departments and moved closer to Canada in North Dakota.
Many years ago I worked in the TV trade where we used conductive paint to rejuvenate remote buttons.
My first computer was a 6502 based Acorn Atom which I built from a kit. On a Saturday evening the computer was built apart from the keyboard when I ran out of solder. In those days nowhere was open on Sundays so no new solder until Monday. I spent half of Sunday operating the keys by shorting the pads with a piece of wire. Happy days.
Vic 20, that takes me back to the early days 🙂
gotta love seeing those commodore computers.
Most of the chips were mid to late 1981. I had a VIC-20 that was given to me by my mom's boss who got it as a "free computer" for attending a seminar. This was when people were already running Windows, so a bit of a let-down I suppose. Mine would overheat and shut down unless I kept my finger on the 6502.
Had one of these many years ago…….While off work with a damaged wrist in plaster, I spent my time working on a programme for trigonometry calculations…..All done now days with apps….. But great times and perfect way to take mind off the the damn pain LOL…