A new endevour

[SpidersWeb]

Oh crap I forgot to update this thread!

No it did not but if you plug the yellow connector in to a speaker channel you get a steady buzz - indiciating signal.
So I think there is life in it, just a bad chip, trouble is I need more donors to fix any problems I find so it's just sitting there at the moment.
I don't like opening things unless I have parts/a plan because they tend to remain open until solved.

I am hoping to fix it or for a working base unit to come my way eventually, let's me keep a bit of retro in my lounge.

[Carcenomy]

Yeah mine is a lounge dweller too, gets plenty of attention that way. Audio buzz means SID is getting something, any hint of VIC activity (even a flicker then black beats nothing!) if so, start with the PLA I guess.

[SpidersWeb]

There is no flicker or random colours/characters tho, even doing the 'off and on 5 times fast' trick. It's all black.
I'm using the monitor out to RCA plug though, not the RF if that makes a difference.

I was quite suprised when I looked up games for the C64, some were pretty impressive considering the type of machine it was - didn't even know Testdrive was C64 too!

[Carcenomy]

Yeah the C64's epic sales numbers are well reflected in its humungous software library - its software truly is its biggest advantage over other 8s of the day by simple quantity. Half of it can be utter rubbish but there's some stunning gems out there. Flaming frustrating that I can't load any of it now though!

Alright, let's see if we can't figure out your issue. Let's start with more description of what model you have so we know what to start poking under the cover. Pop the sucker open and get a board assembly number, and the board revision details from on top of the cartridge port. Let's hope for your own sake you haven't got one of the later revisions (C64E or C64G) as they take completely different ICs to the earlier models. My 64Cs are both C64B3, the last of the early boards and parts-compatible with earlier breadbins.

Once this is a known factor we can work out which chips to start fettling with to get some more lifesigns!

And if you want that 1541 tested, bang that big girl in a box and send it to me. If I can acquire an alignment floppy could get all three of mine aligned using yours as the reference if its condition is as good as you reckon!

[SpidersWeb]

I've got a later revision, C64E. Was going to change the RAM (because I have spare 4164's) but it uses 41464 chips - 4 bits wide. So couldn't attempt anything. But after disassmbling I worked out I wasn't pushing the video connector in far enough, and I was eventually able to get some screen output.

I get mostly black screens, but some times random characters and on a few occasions white screens.

Here is a video of me being a bit of a diddle and showing what the output looks like (sometimes)
http://www.youtube.com/watch?v=SKWkPHqoQ4Q

Edit: and when I mention the keys, it wasn't me, they came in a bag and when I was in the boot the other day I noticed them

[Carcenomy]

64E... lame, I think that's about the board revision where they went SuperPLA. Can't offer you sheeeeeit in the way of spares then, mine are all older model. Tried any cartridges in it?

[SpidersWeb]

I do have some cartridges, will try that tomorrow (I just packed it away )

I noticed while looking at it again, one of the memory chips was replaced at some stage (has one Mitsi 15ns and one NEC 12ns). Since they're cheap I might order a pair of those. It's also got an aftermarket RF unit attached - so possibly the built in unit failed at some stage.

[SpidersWeb]

Do I win a prize?



It turns on, stable boot everytime now, with or without a cartridge.
It's a bad solder joint somewhere, pressing firmly on the chips did nothing earlier, but I did it again anyway after I'd removed the board from the case, powered it up and it's 'fine' now.

One problem though, the spring under + is gone, so I have to somewhat type upside down, but I did make a little basic program nonetheless.
Think I need another C64C to finish this one.

Edit: and the bad connection is definately to do with the memory or controller - first boot I had 1Kb free - pressed again - reboot and now it's reliably 38911 free.

[SpidersWeb]

I see a C64C on trademe with working keyboard from painterman (local) which should be nice - even if it does not work I can steal it's keyboard.
Also my A2000 keyboard adaptor has arrived - lets you use a normal PC 104 enhanced keyboard on the A2000 - Windows key is Amiga, and little shortcuts like pressing Pause twice does a reboot etc. Cost around $50 but way cheaper than bringing in an A2000 keyboard.

[Carcenomy]

You should get hold of Alan Gilchrist. Last time I was poking around in his shed he still had a couple of A2000 keyboards... and I probably should have told you that BEFORE you bought the adapter!

[SpidersWeb]

haha well the adaptor works perfectly, so all is well.
I've just given the Amiga it's own space in the office so it's permanently setup. I opened it up and all looks well, couldn't see the battery but gave it a hand rub and didn't get any goo/residue on me, so that's good. It didn't have a bridgeboard installed but DID have an ISA card - an early 90's "works with everything" style 8bit ISA OAK adaptor - MDA/CGA/EGA/VGA with 256KB DRAM. Nice.

[caluser2000]

The OAK card is a good find. Had one of those in my 286 back in the day. Pretty well bullet proof compatibility wise.

[Carcenomy]

http://www.amibay.com/showthread.php?t=30904

Just sayin'.

[SpidersWeb]

haha cheers, but I'm good, I have an actual PC-XT right next to it and I really needed a spare ISA card that doesn't have trippy VRAM.

Have got some new software for it though, F19 Stealth Fighter boxed and Harpoon boxed (which I got for $5 at a rubbish dump store!). It's setup permanently in the office, but if I can't make more room when I get the last piece (case/PSU) for my 5170 I may need to sell. Actually have a couple of machines I want to sell, but think the price I'm willing to part with them for is probably more than anyone will want to pay :/