C64 mishap

PymerOne

Noob pur sang
AmiBayer
Joined
Jul 16, 2010
Posts
515
Country
Netherlands, Europe
Region
NoordHolland, Far side of civilisation's border.
Dear All,

recently lotsa retro thingemagic in my house starts breaking up :(
C64 and c128 both suffered from quality loss in picture.
Now all of a sudden it works again (with c64...didnt test the c128 yet).
While testing joystick refused to make the sprite move up, other directions no problem :(
Other joystick, same problem.
Seems to me problem is in the machine.
Please help me identify which ic to check.

Thnxx,
PymerOne.
 
If I am not mistaken, the CIA chip 6526 handles the joystick port. I believe there are 2. I would check both. The 6526 is still available, check the net. I would download a schematic as well to identify any damaged lines.
 
Last edited:
yep does sound like the 6526.you might also want to check your power supply,yes i know its tedius but worth it.
 
Have you also checked the pins in the joystick ports?
 
Dear All,

i did a few quick checks:
few joysticks, few psu's, a few pieces of software.
All joysticks worked OK in port1, tested these with both psu's.
None of the joysticks reports "up signal" when in port2...regardless of which psu is used.
btw, tested port 1 with DRUID, tested port 2 with Flash Gordon and leviathan/legend of kage.
lateron i typed this snippet of code which clearly showed me up on port 2 was not available.
Code:
10 print chr$(147)
20 print "port 1 : "peek(56321),"port 2 : "peek(56320)chr$(19)
30 goto 20
Soooo...next step is check for portpins missing/unconnected, caps exploded, tracks burned or cia 6526 chips in distress.
Too bad i am messing up seasons...this should be winterfun, so i could play outside in summer.
Thanxx all sofar for your great technical assistance :)

Grtz, PymerOne.
 
Just swap the CIAs. If the joystick starts working, then the other is broken. Saves you the trouble of checking burnt lines. The other CIA affects other areas of the C64 so if you exoerience other weird behavior that's another pointer to CIA being bad.
 
Dear All,

much to my disgust, most chips (including both 6526) in my C64 are surface mounted :(
I am gone have to find me another machine.
Thanxx again All for helping :)

Grtz, PymerOne.
 
dont throw it away if theres still working parts on it(not that you will)because de-soldering the through hole parts isent that difficult if youve got a soldering iron.
 
dont throw it away if theres still working parts on it(not that you will)because de-soldering the through hole parts isent that difficult if youve got a soldering iron.


Soldering iron and a bit of solder braid is all thats needed, and a tad of patience ofcourse...;)
 
dont throw it away if theres still working parts on it(not that you will)because de-soldering the through hole parts isent that difficult if youve got a soldering iron.


Soldering iron and a bit of solder braid is all thats needed, and a tad of patience ofcourse...;)


yep,agreed you never know when youll need those parts:)
 
Dear All,

point about spareparts taken...i will buy 2 certified working c=64 machines, and donate my c=64's to the club's repaircrew.

Yesterday i worked on my A500 a bit.
It has KS 2.04, a JKSCSI sidecar, a KCS PowerPC and diy goliath PSU.
I had it left for dead, changing harddisk didnt go wright a few months ago.
After fiddling a bit with it, inserting the original 50mb disk and reseating all chips it works :)
Have to admit, its not rocketscience and i haven't performed brilliant actions, but it did made me feel real good to see it boot :)
Succes made me overconfident, so i attempted to get the PowerPC running.
Copied the original KCS system/install disk to a workdisk.
Installed the KCS thingemagic to HD.
Downloaded msdos 3.3, wrote it to a doubledensity disk.
Started the emulator software on the A500, it presents a black screen with "insert systemdisk and press return".
Well whaddayaknow....with the msdos 3.3 disk it reads a bit and says "invalid systemtime, enter new time and press return".
The standard date, time and dir commandos work :)
Ehrmmmm...im no expert on this, but this seems to me like it works :)
Some day soon I'm gone try again to put a larger harddisk in the sidecar, and make it "dual-boot" or "multi-homed".
Hehehe gotto find me a copy of windows 3.11 or maybe an even more ancient version to install on the pc partition :)

't was a good day indeed :)

Grtz, PymerOne.
 
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