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Sunday
Oct132013

Refurbishing a Commodore 64

I recently was able to acquire a nice piece of my childhood, namely a 1983 "breadbox" Commodore 64. I used to have one as a kid. It was the very first computer I ever touched, and was basically responsible for getting me into the IT field and programming in the first place. Then my Mom gave it and all our games away to a friend while we were at summer camp, thinking we wouldn't mind since by then we were all up into Super Nintendo and such. Having the highest number of sales (and a 40% market share) of any single model home computer of all time you would think they would be a piece of cake to find. They seem to always be kicking around EBay, but the last one I bid on ended up going for WAY over what I was willing to spend. I think it was around $350 for the main unit and a tape drive, no cables. Ouch.

Last week, I got lucky. An internet forum acquaintance had a VIC-1541 disk drive kicking around in his attic. He offered it up if I was interested, so I had it shipped. I then started poking around EBay again, and ended up winning this unit for just over $12, condition unknown. There seem to be a lot of "parts" C64s on the market, so I wasn't expecting much. Boy did I get lucky. A few more good bids later, and I'm in business.

First thing first: I needed a power supply. The C64 uses a 7-pin DIN connector to provide both +5VDC and 9VAC to the mainboard. I guess the original power supplies were notorious for the regulators burning out, and taking chips with them. Since this fact troubled me (and was basically moot since I had no cables), I looked up the pinout and built my own. A trip to Fry's netted an 8-pin DIN for about $0.59, and the center pin was easily removed with a bit of violence. I had plenty of decently beefy 5VDC wall warts lying around, and DigiKey had a 9VAC one for about $7 after shipping. A bit of heat shrink and some soldering, and I was ready to test the unit out. To connect to the one TV I had with a standard antenna A/V connection, I used the same setup I usually run my Nintendo on. Cross fingers, throw switch.

'Tis the perfect amount of bytes. This means the RAM is most likely still good, so yay on that front!

Trying the keyboard out, I noted many of the keys didn't work most of the time, and when they did there was terrible debounce. So in I want with the screwdriver to see what I could do! I met with a dire warning from beyond time:

Oh man, there goes my 30 year old warranty...

They keyboard is just a bunch of simple conductive pads, similar to a TV remote. A bit of a scrub with a pencil eraser and some alcohol and they shined right up.

Popping the unit back together, I gave it a go with some quick BASIC commands. Flawless!

Next I was dying to test out the SID, Commodores legendary audio chip. These things are crazy hard to find these days. Folks use them in synths and other audio devices, and the demo scene is still going after all these years. Unfortunately, they burn out rather easily. Since there's no real way to make more of these babys every burned out chip is another chip less to go 'round. I found a nice 1 line BASIC audio demo and typed it in. Nothing. Damnit. Luck for me a batch of 10 happened to be found on a warehouse shelf, never before placed into any unit, and tested by the seller. I picked up two.

While I wait for a replacement SID, I decided to clean up the entire unit (full of dust bunnies) and see what I could do to extend the life of the other chips.

So far all I have done was verify voltages with a multimeter, re-check the SID output with a scope just in case it was my TV or something, and added some old heat sinks I had lying around to try to keep this old stuff cooler.

I plan to salvage or fabricate a few more heatsinks for the ROM, RAM, and kernal chips. I would like to make an s-video cable to clear up that picture a bit. I have also begun to work on an Arduino/Rasperry Pi solution to emulate the 1541 disk drive I have, but allow me to read in images off USB or an SD card. More on that to come. Right now I am pretty stoked to be at this point.

Tuesday
Jun082010

Adding a new SSD to your EeePC 901

I meant to document this months back, when I actually performed this operation on my "FrankenEee", but I guess I was just in a post funk.  No harm done, I shall make up for it tonight!

I decided that the one thing I wanted to change about my EeePC 901 was the tight storage, and happened to hear promises of significant speed boosts as well from ActiveMedia's "SaberTooth SS" mini SATA SSDs.  At the time, I hadn't heard much about them, as everyone was scrambling for information on the hot new Runcore SSDs.  I bit the bullet, and picked up a 32GB drive for I believe around $129.

Shipping was fast from Amazon.  Came all nice and double wrapped.


Standard anti-static bubble packaging keeping the drive healthy through it's trip.  Which is great, since these things are not exactly cheap.



Installation was really simple.  Two screws under the Eee hold the access cover in place.  Simply remove them, pop the panel off with a small screwdriver, and you have access to RAM, the WiFi card, and the SSD.  Two more smaller screws hold the SSD in place.  Remove them, and carefully pop it out.  Then simply replace it with your spiffy new one.  I also took the opportunity to swap out the RAM for a 2GB Kingston stick.

Ignore the crazy antenna wiring off my NIC, I had previously swapped it out for an 802.11n band card compatible with Backtrack4 for playing with wifi injection, and added an external RP-SMA connector.


Now replace all the screws, and close the panel back up.

Now was the part I hit a small snag.  Upon booting, the BIOS would not detect the Sabertooth drive.  I disabled the internal 4GB SSD, and rebooted.  Entering the BIOS again, I now couldn't see either SSD.  After a few minutes of head scratching, a helpful post on the EeeUser Forums suggested I try resetting the BIOS to factory defaults.  Once I did that, both SSDs were detected, with the Sabertooth as primary (as I was hoping for).

I installed Eeebuntu 3 Base, and checked out my new storage options.



After all was said and done, I now sport a tri-booting Eeebuntu/WinXP/Backtrack 4 laptop that weighs next to nothing and fits very comfortably at the bottom of my backpack.  The extra space is a wonderful change after getting used to fitting my whole system on the 4GB drive, and there is a noticeable speed increase for both reads and writes.  I couldn't pin down a standard benchmarking tool that everyone would agree was valid and would run under Linux, but I can definitely tell the difference.

In short, this is a simple and effortless upgrade to your netbook, and it's even easier to afford nowadays with SSD prices dropping.  Plus while you're in there you can bump the RAM up past the 1GB limit Microsoft is imposing on distributors, and maybe even upgrade your WiFi capabilities.