Indivsion AGA artefacts appearing on the display

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Don't Panic. Please wash hands.
  • Hi,

    When using the Indivision AGA on my A1200 artefacts are intermittently appearing on the display within workbench. See attached photos and video within the link below, can you help me resolve please?




    Video link:

    https://drive.google.com/file/d/1W4bEWLlYleA6MB4wlWEZhG7PEwJVlfsv/view?usp=sharing

  • That's not an Indivision problem, but a problem of the computer that merely *shows* with Indivision. Please read the manual, especially about the advanced settings of CCK pull-up and CCK capacitance.

  • I have read the manual and in the the advanced settings I have tried different combinations of CCK pull-up and CCK capacitance with different results but nothing solves the issue.

    The A1200 is a ReAmiga 1200 done by John Hertel, new quality capacitors and resistors were used so I doubt it is the Amiga.

  • The A1200 is a ReAmiga 1200 done by John Hertel, new quality capacitors and resistors were used so I doubt it is the Amiga.

    It is very likely that it's the Amiga, as the CCK pullup/down values chosen for Indivision AGA MK3 are of course geared towards Commodore-made A1200s. The ReAmiga is a totally different thing, and a mere change in the pull-up resistor for the lowest ram address line changes timing between RAM and Lisa (that's where it goes wrong).


    If you have a 15kHz monitor that can display these resolutions, you will clearly see that it will also show these artefacts. Please have them corrected by John. I can only tell you where the issue is, but it can certailnly not be my task to correct it if it's not in our product.

  • Once again, there is no causality, other than "you are using this screenmode because Indivision can display it". The cause is the A1200, that has been known for many years.


    And no, the ReAmiga is (and cannot) be an exact copy, as the component tolerances are definitely not taken into account. The only thing you can say about the ReAmiga is that it has the same problems with double-CAS modes as many other A1200s. Proof: A monitor connected to the DB23 monitor port shows the exact same artefacts.

  • Hi, I'm using a MK3 on my ReAmiga 1200 board too and have no display artefacts or problems at all, the MK3 for me is a solid product, as well as the ReAmiga board. Could the problem be your cable or do you have another monitor you could test with?

  • Could the problem be your cable or do you have another monitor you could test with?

    No. The problem is a shifted CCK, trust me. I've done extensive measurements on the A1200 and fixed all artefacts with CCK-moving components, sometimes with increasing the Vbb capacitor for Alice.


    Besides, there is no "one" ReAmiga, If there are 50 ReAmigas out there, then it's 50 different computers. Not a single one is using the exact same components, and exactly zero of them are calibrated to any timing constraints.


    While the customer is not willing to accept (or even fact-check me) that the artefacts also show on a DB23-connected monitor, any further discussion does not make sense.

  • Of course I am willing Jens, I'm not fussed how I just would like a solution.

    Unfortunately I do not have a DB23-connected monitor hence the reason why I have the Indivision scandoubler.

    What do you mean by fact-check me?

  • Guybrush86 did you ever manage to fix your problem? I have a re-Amiga on the way and would love to get an MK3 for it, but not if its a lottery ticket.

  • The last reply was more than 365 days ago, this thread is most likely obsolete. It is recommended to create a new thread instead.