Recent content by Pet Rescue

Hi Frank, thanks for the reply. Here's the board:- Well I was probing the board with my multimeter, testing diodes and transistors using the first board type schematic off Zimmers, the one with the picture of the PCB with component location. I tested each diode and transistor etc and they...

Hi All it's been a while, I decided to dust off my 2001 Chicklet and have a go at repairing it. The story so far has been a toughie!! I have repaired it, it runs for a while then fails. I repair it again and something else fails. I don't think it likes being switched on, anyway my first lot...

Hi all I have a quick question regarding a 6550 Ram adapter that I have seen on Nightfallcrew website.http://www.nightfallcrew.com/19/08/2014/commodore-pet-2001-6550-ram-adapter-by-xad-manosoft/ It is regarding the address lines on the 6264 Ram chip, address lines A2 & A3 joined and A4 & A5 are...

I have been reading up on computer systems when I stumbled across this excerpt in a book:- "MOS Technology has announced the planned introduction of the 6509 IC which will combine the 6502 and 6530." Is that what the 6509 actually is or are they mistaken?

Here's the schematic Dave:- I was wondering because the difference in schematics for 2114 and 6550 video rams, the only difference in the circuit was no clock signal to the 2114. So I was wondering why the designer combined the signal when commodore disregarded the clock line for the 2114...

Hi Dave I've just had the logic probe on the output of pin 13 SD7 on C4 the video RAM 6550 and it's pulsing. I followed it to pin 2 on C1 the 74ls74 which I believe acts as a Master/slave flip flop circuit from what I've read. But the output is constantly high on Pin 5 which I would expect to be...

Hi all it's been a while since I've had a project. I have recently aquired a 2001 chicklet pet with the 320008 assy board. It was a non working machine that showed garbage. All four voltage regs are around 5v (4.95v & 5.05v etc) I removed the PIA's and all 6550's except I1,I2,J1,J2. I subbed the...

Hi all it's a change of machine from Pet's at the moment to an Amiga 2000 that's driving me mad! I have used it and all appears to be working fine, except the expansion ports. I have a gvp hc+8 hard drive card with 2mb memory and an xt bridgeboard installed. I have tried to use the install...

Heads up fellas there is another P500 up on ebay, it is not tested as per usual the seller does not want to risk turning it on :o and price is quite high at £499.:wow: (well for an untested one!)...

Just a quick heads up there is one on ebay ending today! http://www.ebay.co.uk/itm/COMMODORE-P500-low-serial-number-rare-vintage-computer-european-pal-/121677280015?pt=LH_DefaultDomain_3&hash=item1c5487f30f

Hi I have a few questions about the Superpet:- How rare are they? How much are they to buy? Can it work without the dongle in the top board? Do they have two or four switches on the side? Can you obtain the side switches and roms? Where do they plug into on the three board earlier type...

Just had a bit of a shock by this listing on Ebay, are they worth this much or is the seller just being hopeful? http://www.ebay.co.uk/itm/ULTRA-RARE-CMD-CREATIVE-MICRO-DESIGNS-RAMLINK-RAM-LINK-16MB-COMMODORE-64-128-/321733174672?pt=LH_DefaultDomain_0&hash=item4ae8caa590

Points towards a bad RAM initially as first thought, piggybacking doesn't always show a bad RAM chip. Personally I would remove all of the old RAM chips and socket them for the replacement 4164's as they are cheap and plentiful.

Thanks jltursan, it's taken me around six years I think of actively trying. They just seem to go for silly money at times! I'll be asking more questions on programming it next so!! My next attempt to add some pictures Yes it's working the startup banner and message Daughter board header...

Yes!! I fixed her yesterday but I had to put a few things right I did wrongly (though done with good intentions) :happy2: The problem was in BANK 0 U71 was faulty. I found the fault by first having to desolder the ROM daughter board, I had to do this because there was not enough clearance to...