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Mq.

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About Mq.

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    Poznań, Poland
  1. I had the same issue. In my case it was bad contact in socket of basic or osrom chip. Remove chips from sockets and put them again.
  2. So check the Freddie chip in another motherboard, probably it is dead Freddie which is common damage. By the way I told you past before, there is a clock problem if you have no reaction on video output at all.
  3. You have to looking for normal crystal 14,187576 and not for integrated oscillator/generator. Anyway it's hard to find and buy it, then you should be sure it is damaged before you ride the long way round the world to find it:-) You must to check it by oscilloscope or logic analyser or frequency meter. Just check if there is any clock signal around the Freddie chip.
  4. If you have a black or red screen, then it could be some chip damaged. But if you have no video signal at all, then check 14MHz oscillator. I fixed two dead motherboards by replace oscillator.
  5. I don't know if it will be good idea in this case, but I know one reverse method. I didn't try it yet, but I was reading on some guitar forum, that some people puts a white guitar pickups into strong black tea or strong cofee for a few hours to look them older. I think maybe it is good idea to try it with a small unnecessary piece of plastic for test the method. It's simple to test it.
  6. @guus.assmann: Thanks for the hint. I know in this circuit it is important to have proper propagation delay times to get proper phi1 and phi2 signals. I think it is the reason to F or S series may not work, because they has to short propagation delay time. The LS series has the same propagation delay as the HCT series, so it's equivalent in this case. My friend used LS series in his adapter board, but that adapter was tested only with 65XE/130XE motherboard with ECI and 4-bit RAM's - and works fine. And You are right: if You have DIL chips in the sockets, then You can try few different IC's. Anyway, I think if there are so sensitive timing, then maybe the circuit needs to be fine tuned to every specified machine. Adapter boards I designed and ordered, I shipped to few people, and they will build few adapters more. I think they will test them on some different motherboards in the near future, so we will get some more information about that.
  7. As I wrote, I tested the adapter on two 65XE motherboards without ECI (with eight 1-bit RAM chips). There were the same PMG issues on the both of them. Then my friend built the adapter and test it on the 65XE/130XE board with ECI and 4-bit RAM chips, and he told it works fine. So I found the same motherboard, and my adapter works on it fine too. I attach the picture with issues on no-ECI motherboard, and second picture without issues on ECI motherboard. I will check the numbers on Freddie's chips later, or maybe tomorrow...
  8. 74HCT541 in SMD are in DW package, which don't fits between 6502 and Sally socket pins at all. Paradoxically in this case 541 in DIL package is better choice and takes up less space than SMD chip. That's why I purposely used SMD for 74HCT02 and 74HCT74, but DIL for buffers chips.
  9. Hello. I'm the designer of that new PCB. The main purpose of this project was to build it for fun, and to use 6502 as a replacement of our beloved Sally (for fun too:-)). Some people on our atari.area forum found cheap UMC6502I (Sally) in China on eBay I believe, and they bought some of them. Unfortunately the seller sels them 6502/6502A - not Sally. So we found that we can build adapter using the solution from Atari 800 schematic for generating HALT signal. I designed PCB, built one board, and succesfully launched it. But... It works perfectly on Atari 65XE/130XE motherboards with 4-bit RAM chips (tested on two such boards without any issues). There are issues on Atari 65XE motherboards with 1-bit RAM chips, and without ECI. The issues was the same on two such motherboards. Generally everything is ok, but there are some problems with GTIA. In some games P/M graphics disapear and there are no players sprites. Motherboards and GTIA's works perfectly with original Sally. Any ideas what is the diffrence between that motherboards (65XE with/without ECI) which causes that problems? I attach a schematic and pcb design of the adapter. (sorry for my english, I hope You understand what I wrote and what I mean:-))
  10. So you can add them via emulator as ParanoidLittleMan said. In the emulator You can add some windows folder as hdd, I suppose. Then You can copy files You want from that folder into .st image by emulated machine. Another way is to use the program I previously linked. I'm useing it that way, that I pack files into zip file via windows, then I convert such zip file into st file. I don't use it to edit existing st files, so I don't know how to do that, and if it works.
  11. Partially You can use MSA Converter 2.1. I'm using it sometimes and works very good for me. In Windows You can add to zip file some Atari files like programs, folders etc. and then convert such zip to msa or st file. But I don't remember if You can edit st file... Check it out here: http://msaconverter.free.fr/index-uk.html
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