My A500 "project" pics, details, build log?

[AmmoJammo]

I've recorded the Bolder Dash II music, is there anywhere good to host wave files? about 4 meg each.

[AmmoJammo]

youtube, with a stolen screenshot?

http://www.youtube.com/watch?v=94aTHJHgQSk

http://www.youtube.com/watch?v=pmN7FwRLz-c

[AmmoJammo]

I put the good chip in the bad motherboard... sounds good...
so, I have two bad SIDs...

[AmmoJammo]

they are all early SID chips, and I've been using the same power supply for all testing.

I have four chips total, two seems to work, two are crackly..

On another, related note, I made an XA1541 cable today, using 2N7000 mosfets from Jaycar, 60 cents each, needed four, plus a 25 pin male DB connector, already had a backshell, and I cut a spare floppy cable in half.

Well, it refused to work in Windows 7, so I pulled out an old Windows XP machine again







SO! any good games I should get? or even music demos? something to test the SID chips fully?

[AmmoJammo]

Are there any demos like on the Amiga?

[AmmoJammo]

Here's SIDBench

http://dl.dropbox.com/u/71121999/c64/sidbench1.d64

This page might be useful during your testing:
[url]http://ploguechipsounds.blogspot.com.au/2010/05/one-page-basic-sid-benchmark.html[/url

Thanks, at least theres a sound file on there so i know what Im listening for

[AmmoJammo]

Btw, I found a Seller on fleabay with a nice pack of replacement BreadBin c64 Caps and Voltage regulators for $10aud delivered so I grabbed a set.

http://www.ebay.com.au/itm/170858848148?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649#ht_500wt_1130

Dont forget the 4700uF, 16volt capacitor, and 5volt regulator in the power supply itself.

Unless you have a power supply that you can't open...

[AmmoJammo]

depends if it has screws or not :p

[AmmoJammo]

I have three black butter containers, and a beige one with the C= logo on the top. No triangle power supplies in my collection.

I assume the triangle can be opened, might be worth checking what capacitors it has before buying anything

Probably easier replacing the cap in the power supply as its only a single sided board, so, yeah, fairly easy.

[AmmoJammo]

they aren't triangular?

from what I can find there are four designs, these three, which I believe are also available in black,



As well as the design I have.

I believe the middle above is completely sealed, apparently the wedge is known to overheat, and I'm not sure about the other?

[AmmoJammo]

...I'm sure it does... lol

It'll have a 4700uF, 16volt capacitor in it, but there seems to be two different board/heatsink designs.

One will require you to unscrew the regulator from the heatsink, the other won't

[AmmoJammo]

These are the two "bad" motherboards I'm still working on.



The bottom board is completely dead, and I'd planned to desolder the ram from that board, and fit it to the top board...

except, the bottom board is a much higher quality PCB, the top boards bottom layer is completely delaminating, while the bottom board is in perfect condition.

So, the plan now is to desolder the PLA from the dead board, because someone decided it didn't need a socket... fit a socket, and try the PLA from the bad ram board...

fingers crossed!

[AmmoJammo]

:knuddel:





I was a bit worried about what I might find inside, as the back shield was very rusted... sure looks like its never been opened, or cleaned... it does however appear the keyboard is slightly bent...



Lovely Revision 5 motherboard inside


but whats this? thats not a chinon drive... interesting


any one have any idea what this modification did?

[AmmoJammo]

My most recently acquired A500 does funny things.

I've plugged in a modified floppy drive, booted flimbos quest... then realised I needed a keyboard.

SO, powered off, booted up, went to press F1, keyboard didn't work, then I realised the power light had gone off.

So, tried again, this time while booting I watched the lights.

It appeared to be going fine, till both lights went out, then the power light seemed to become the floppy activity light.... ah?

Tried booting again, except this time both lights went off, while the activity light on the floppy drive itself remained on, but nothing booted... unplugged the keyboard, and it booted fine?

[AmmoJammo]

Swapped keyboard, same issue.
swapped odd/even CIA to opposite locations, same issue...

hmm...

[AmmoJammo]

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