I guess the biggest issue is not the cost or the availability but the space? Since you already know most of the boards where the MK2 has to fit, isn't it possible to extend the PCB a little bit at one end?
I really don't want to extend the PCB, since doing that will cause potential problems in some systems. Also, with the MK2 a primary goal is the 40-pin DIP package. Also, that MegaChips IC is 12mm x 12mm, which is almost as big as the FPGA itself, so it would be a very big extension.
I searched in other forums:
Atari 8-bit board, Sophia Rev C 2018, has DVI out:
They use a ribbon cable to a board with DVI socket.
Thanks for the link, that board is interesting. The part selection seems a little odd though. The Silicon Image IC is about $10, seems hard to find, and only provides parallel-RGB data to DVI conversion. The Altera CPLD is around $20 for just 400-macrocells. At that price you are into a pretty good size FPGA that can easily generate the DVI video directly. I think the creator of the board could reduce some cost and complexity for himself (herself?). For the record, I'm not judging, just making some observations.
As for the ribbon cables, I looked at those connectors, they are the Micro-Match series by TE. Although they are small, they are still large compared to the MK2, and I would have to provide both ends of the connection which means designing and building a daughter-board as well. In addition, those connectors can get expensive when you price the pre-made cables plus mating connectors on both ends. Also, on the Sophia board the grounds are missing for the LVDS pairs, which I suppose you can get away with (it seems to be working), but personally I would not omit them and that makes the connector even larger.
Right, I use similar devices regularly, but I am wondering if the F18A Mk2 could put the audio stream into DVI for a passive converter to change the DVI output to HDMI, but still be usable with DVI monitors.
Yes, DVI monitors *should* ignore the audio data islands depending on their placement in the data stream. I say "should" because it probably depends on the monitor. The DVI monitor I'm testing with ignores the audio data. The bigger question is, even if I generate DVI video signaling, if I add the audio data islands have I crossed over into license infringement?
What about just putting a FPC connector on the MK2 and providing a ribbon cable? You can then leave it up to the purchaser to buy the HDMI CYFPV connector for about $5. If you search ebay or amazon with the term "CYFPV" you will quickly find what I am talking about. Since you have nothing but a ribbon cable connector, I would think you would be safe from the whole HDMI issue.
Thanks for pointing out those connectors and cables. Because the demand is high for those parts, they are easy to get and cheap, which makes it a possibility to consider this option. The main problem with the FFC / FCP connectors is, yet again, their size. The ones you see on those boards are 15mm wide minimum, and do not fit between the PCB pins of a DIP-40 IC (the DIP-40 pins are 15.2mm (600 mils) on center). However, I can get the connector in a vertical-mount which reduces the size to about 10mm x 4mm, which is still rather wide but possibly workable.
This works as a legal solution.
As a technical solution, it may work if it can be fitted onto the PCB. That is not for me to decide.
That is good to know! I wonder if a USB-C connector also provides the same legal solution? Do you know for certain one way or another?
Even though the USB-C connector is also 10mm wide (total PCB footprint), so the same size as the FFC connector for the ribbon-cable solution mentioned above, is does have an advantage of providing a USB-2.0 connection that I might be able to utilize for firmware updates (however that also requires yet another chip). Passive USB-C adapters are also readily available in the market right now.