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  1. daver2

    Cbm 2001 Pet strange boot

    Good point, I was going to mention that a while ago and forgot. The probes cone with plastic attachments. They cover the GND ring of the probe to protect it from shorting against things. In addition, one of the plastic attachments helps the probe to stay on IC pins and not slip. Are you using...
  2. daver2

    Cbm 2001 Pet strange boot

    Can you video the following signals please and indicate the frequency (if the signals are stable). B2/6. A3/11. A4/1. A3/10. A4/3. A4/6. Dave
  3. daver2

    Cbm 2001 Pet strange boot

    They are fine. Dave
  4. daver2

    Cbm 2001 Pet strange boot

    Yes, You can also check A3/4 and B2/5 at the same time. These are an inverted BA11 and can be tested at the same time. Thanks for posting the image, that helps me help you! Dave
  5. daver2

    Cbm 2001 Pet strange boot

    They look fine. I am not sure why your frequency meter is not stable. The oscilloscope trace is rock solid though. You may need to read the manual to identify how the internal frequency meter works and whether there is any specific set-up required for it (e.g. oscilloscope Y position or...
  6. daver2

    Z80 assembly inconsistency

    I fully agree. Dave
  7. daver2

    Cbm 2001 Pet strange boot

    Are you reading the frequency from your inbuilt frequency meter or the oscilloscope trace? How is the frequency changing on A6 / UD9 pin 2? Are the other address pins indicating a stable frequency? Can you post a video from the oscilloscope for A5, A6 and A7? Dave
  8. daver2

    6502 Assembly Language Question.

    Self-modifying code is the spawn of the devil and should be avoided at all costs! However, if you must do it, you must do it... I suppose my dumb question would be "why not use page 0"? That is what it is there for... If you must use self modifying code, try and use a 'generic' subroutine to...
  9. daver2

    6502 Assembly Language Question.

    Correct. You either must use page 0 or self modifying code. Those are your only two options I am afraid. Dave
  10. daver2

    Cbm 2001 Pet strange boot

    Just got back from my business trip... If you go back to post #1,584 I asked you to measure the frequencies. ScottishColin was kind enough to test his machine and post the frequencies that he observed from his machine (1,591). You have the correct equipment to perform the test now, so why are...
  11. daver2

    CBM 8032 "factory upgrade" to SuperPET

    There is a 6502 BASIC memory test somewhere. You can specify the start and finish address. For the SP9000 the start address would be $9000 and the finish address would be $9fff. You can select the bank of 4K out of 64K by poking the memory address for the bank switch register and run the memory...
  12. daver2

    CBM 8032 "factory upgrade" to SuperPET

    I am looking at your posted photographs and seeing the duplicated text and error messages that are displayed. This is indicative that something is clearly amiss between the SP9000 and HOSTCM to me. I am sure you have read this...
  13. daver2

    Cbm 2001 Pet strange boot

    I have checked myself, and the firmware for UD9 that has been burnt looks correct to me also. Based on that we are looking at the CPU -> ADDRESS BUFFERS -> ROM (UD9) -> DATA BUS -> CPU interface, along with the UD9 address decoding - and any potential bus contention. Assuming the CPU address...
  14. daver2

    CBM 8032 "factory upgrade" to SuperPET

    OK - I understand more now... So, I am not sure what you are using the waterlooMonitor 'p' command for? It looks like you are trying to start HOSTCM on the remote machine via the SuperPET using the serial port. Is this correct? If so, you are trying to use the serial port for two different...
  15. daver2

    CBM 8032 "factory upgrade" to SuperPET

    You go into the Waterloo Monitor and type 'p'. You log into your remote machine. What do you then type to perform the load? This is why I am suggesting using HOSTCM on your remote machine, that is guaranteed to work (he says)... Dave
  16. daver2

    Cbm 2001 Pet strange boot

    Yes, we still haven't found the root cause of the original instability and crashing - so this may still be a factor of course. I am hoping that finding this problem may identify that problem also (we can wish). Dave
  17. daver2

    CBM 8032 "factory upgrade" to SuperPET

    >>> Programs for the 6809 are loaded in the following way I connect my laptop with Linux to monitor in P mode and load files to SuperPET memory directly via rs232 cable. Are you sure that works? I am not... Dave
  18. daver2

    Cbm 2001 Pet strange boot

    Have you tested both the DATA and ADDRESS lines of the ROM like I asked? Your issue with UD9 pin 2 is perhaps more to do with the scope trigger level rather than the signal itself. The signal on the oscilloscope trace seems relatively stable. Remember what I said about adjusting the scope...
  19. daver2

    CBM 8032 "factory upgrade" to SuperPET

    First thing, have you used my PETTESTER ROM to test out the 6502 PET itself? Second thing, I did ask a question back in post #5 about how you are loading programs into the 6809. If I remember correctly, there are some diagnostics for the SuperPET. I can’t quite remember at the moment where...
  20. daver2

    Cbm 2001 Pet strange boot

    I think you ought to put the NOP generator back in and check all of the address and data pins of the UD9 ROM with your oscilloscope. BA0 should be 250 kHz (if I remember correctly) with each higher address line decreasing in frequency by a factor of 2 (so BA1 will be 250/2 = 125 kHz). For the...
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