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About guus.assmann

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  • Birthday 09/23/1957

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    Netherlands City EDE

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  1. For 1.44 MB to work, there's also a Gal that needs to be the right revision. If not, it won't work either. If I'm not mistaken, the one you need is in this .zip However I'm not sure which one to get. And I don't have source code. I did replace that one in my computer as well and also placed the FPU and Gal with that. BR/ Guus GAL.zip
  2. If the capacitors are removed and the resistors and possible coils are bridged, the I/O will be faster. However, the computer will not pass the EMC test. That may cause problems in some case. It may cause RF interference. The 68B21 has some higher drive capabilities. That can also cause more RF. Not always a big deal really. BR/ Guus
  3. Hello, The circuits in the Atari are all 5V. So is the RTC. But it will remain working fine at a lower voltage. 4,5V is well within the safe range. Just make sure that the batteries will not be emptied and start leaking. That would make a terrible mess and now you'll get 3 instead of 1. You might consider putting in Eneloop cells. Then you'll get about 3,6V. BR/ Guus
  4. I own at least 2 of those boards, one with original box and documentation. They were designed for the Mega ST and have this size, so the can be securely be mounted in the computer. There's a couple of standoffs at the end of the board, away from the connector. Also there's some metal shielding. There's a 16Mhz oscillator on the board. I've put a socket in and tested with higher frequencies. Above about 24Mhz there's not much improvement anymore. (Gembench test) The speed is determined mainly by the data transfer between CPU and FPU. BR/ Guus
  5. Sorry, I've only used the board a couple of times using Dos. So I'm not sure about any windows version. BR/ Guus
  6. Hello, Yes, you're right that there's a difference. I'm not sure if the "simpler" version will work. Maybe some specs can be found for the board? (Or the readme file with the software) Both the one in my Mega STE and the one that's not mounted do have an FPU socket. And I also have 1 without the FPU socket. That one is also not mounted. BR/ Guus
  7. Hello, I own a Mega STE with an AT-Speed in it. It does contain a 286 and also has a Chrystal on the PCB. (32Mhz is engraved) And the Atari does run at 16Mhz. Also, there does exist an adapter from the PLCC 68000 to a Dip 64 socket that's specially made for an 286 PCB. I don't have the schematics for either card. The Adapter I've just seen is made by GE-Soft. My Mega STE works well, until I move it between rooms. As long as I don't do that and let it sit in it's own place, it's working happily. BR/ Guus
  8. Have a good look at the Gotek documentation. There's a possibillity to use pin 2 for disk-change signal. That may be of use. (Have not tried it myself...) BR/ Guus
  9. There's an adapter board to interface between the PLCC socket and the DIL socket. However that may be hard to get and can cause contact problems. I have to reseat mine every once in a while. So yes, it will function just fine in the MegaSTE, also if that's run at 16Mhz. The 80286 has it's own clock.... BR/ Guus
  10. Hello, The fact that you succeded is proof that you did it right. And the price for the chips is quite good I think. In future, also look at the speed of the chips. 150nS is mostly good enough. (On 8Mhz system 200nS will also do) On a TT you may want to use 120nS. Erasing depends on the light source. Just experiment with shorter times. If you test before programming, it's ok. One very important thing for erasing Eproms. Make sure they're in conducting foam,all pins must be electrically connected. Failing to do so may destroy an Eprom. Especially the older ones like 2716 or 2732. The even older 2708 will definitivly not survive if pins are not connected. I've learned that in the time that an Eprom costs FL 150 (Current equivalent is $ 150). They were not my Eproms, my manager killed them and I found out why. BR/ Guus
  11. What's the speed of the Eproms? 120nS would be ok. Slower may cause problems. BR/ Guus
  12. Hello, That's a matter of taste. Personally, I like GFA Basic better. (Has lots of examples as well). BR/ Guus
  13. Hello Bikerbob, It is very possible that the revision of the test cartridge is the problem and not the hardware itself. I've had this issue, until I used another (multi) testcartridge. It might need a test cable or another fixture to pass this timing test. Does the testcartridge start the menu? Maybe after hitting the space key? You should be able to do all other tests. However, I cannot tell you what revision to use. (I'm not home at the moment) BR/ Guus
  14. Mostly, if you heat up the label, the glue will become soft and the label will come of more easy.
  15. Hello, I have made a PCB, many years ago, that made it possible to use a 65C02 in the XL's or XE's. And the XL7 is already in this forum, look at the attachments I put in. Schematics and source code are there. Just needs some sorting out. There's "logic" in the file names. BR/ Guus
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