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  1. Replies
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    I thought they got the 8050 interface working....

    I thought they got the 8050 interface working. However I have a 4040 drive and ZoomFloppy does not work with it. It seems they put very little effort into the software debug of ZoomFloppy with the...
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    Il Paninaro, I hope you are taking good notes. ...

    Il Paninaro,
    I hope you are taking good notes.

    Our Sir Dave is turning you into a first class PET Technician. Congratulations!
  3. Yes, he mentioned something called a Pico scope...

    Yes, he mentioned something called a Pico scope that has a stated bandwidth of only 10 MHz. I don't thing he can trust it for seeing the 8 MHz clock. I hope we do not have too problems in the video...
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    Hugo, Wonderful well written technical article....

    Hugo,
    Wonderful well written technical article. Not that I could follow all of it!
    -dave_m
  5. OK, leave them alone for the present. What ROMs...

    OK, leave them alone for the present. What ROMs are on sockets? What is the part number (with dash number) on F9 the kernal ROM?
  6. Replies
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    Great team effort on the video repair! Kudos to...

    Great team effort on the video repair!
    Kudos to Daver, Dwight and Hugo for their expertise and especially to The Paninaro for his dedication.
  7. With the two video RAM chips removed, you will...

    With the two video RAM chips removed, you will get all ones going to the character generator. This should generate a checkerboard pattern on the screen if all is well except for video RAM.
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    OK all ROMs checked good! Of course test could...

    OK all ROMs checked good! Of course test could not check the EDIT ROM. We should be close.
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    OK your Monitor is working OK. And the tests...

    OK your Monitor is working OK. And the tests indicate that the RAM is good. But as the EDIT ROM does not bring up the system, then perhaps a ROM is bad. I can tell that the FD16 sum check on the...
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    Sorry, yes there are four RAM chips for the 80...

    Sorry, yes there are four RAM chips for the 80 column display of the 8032.

    UC4 and UC5 for the even addresses and UC6 and UC7 for the odd locations.
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    I agree, but we could use a better video test...

    I agree, but we could use a better video test signal. If, and only if, the two video RAMs (F7 and F8 ) are on sockets, it may be beneficial to remove them to get a Hex 'FF' to the character...
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    Wow! Good work guys! Raster scan is good. You may...

    Wow! Good work guys! Raster scan is good. You may have issue with Video signal path.
  13. Here are the schematics for the 3000 series....

    Here are the schematics for the 3000 series. Start with the clocks if your scope can handle 8 MHz. It is on Sheet 6 on chip G5-pin3 called CLK8.
    ...
  14. Thread: 8050

    by dave_m
    Replies
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    1,961

    Save machine code in PET to Disk: Get to the...

    Save machine code in PET to Disk:

    Get to the Machine Language Monitor: SYS 400 (gets to a BREAK Instruction).

    .S "0:TEST FILE",08,0800,0C80 (Return)

    This example SAVES to Drive #0 of the...
  15. Good work!

    Good work!
  16. That does explain the 'stuck' screen. Bad screen...

    That does explain the 'stuck' screen. Bad screen memory ($8000) reads by CPU. May be the NOP test is not showing good address signals yet?
  17. Hi dhoelzer, You are getting on top of the...

    Hi dhoelzer,
    You are getting on top of the problems. Great work! But I have always been suspicious of the D8 and D9 EPROM sockets (see message #30). Commodore used cheap sockets and the prior owner...
  18. Yes, in the 4040, the 2332 ROM has pin 21 with...

    Yes, in the 4040, the 2332 ROM has pin 21 with high chip enable and pin 20 is low chip enable, and pin 18 is address A11. What would be the jumper configuration in your adapter? If a 28 pin package...
  19. Does the Machine Language Monitor work? Is there...

    Does the Machine Language Monitor work? Is there a C* in the upper right corner for Call to Monitor or a B* for Break to monitor?
  20. Frank, I assume the board assembly includes the...

    Frank,
    I assume the board assembly includes the programmed EEPROMs? This would be a good solution.
    -Dave
  21. A peer review of this circuit would be welcome. ...

    A peer review of this circuit would be welcome.

    56953
  22. Rick, The problem is that on the 4040 there are...

    Rick,
    The problem is that on the 4040 there are two CPUs (6502 and 6504) sharing the bus, so that the Phase 2 Clock is used to allow the 6502 to use the bus when its clock is high only. The other...
  23. Thread: 8050

    by dave_m
    Replies
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    1,961

    Does the filename on the SD card have the .prg...

    Does the filename on the SD card have the .prg extension? Try it with and without the extension on the filename and see if that makes a difference.
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    Il Paninero, It took only 400+ messages to fix...

    Il Paninero,
    It took only 400+ messages to fix that PET! It was a tough one with a lot of problems. You learned a lot about using an oscilloscope too. You did very good soldering work.


    Let's...
  25. The PIA C7 may be bad.

    The PIA C7 may be bad.
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