Feature Request: Support separate H and V TTL sync inputs

[maxtherabbit]

This feature would be helpful for the Dreamcast, as well as a myriad of retro computers that output separate sync. Judging by the existing design where all sync sources are separated before being passed along to the monitor, it seems like a fairly trivial feature to accommodate. Amazing work so far!

[skumlos]

Yes, this should be trivial besides whatever switching mechanism that would also be "needed" and I will definitely put something like this into this or a future version. I dunno how much it directly helps Dreamcast if the sync from it is whack (as implied by the need of a multivibrator circuit in the vblank period as I understand is present in the RetroAccess cable) but I am gonna look into some of that soon :) and thanks!

[maxtherabbit]

Well I'm no expert on Dreamcast sync, however I do believe that the use of the multivibrator in RA's cable is only needed to recreate the serration pulses during v-blank.

As shown in the attached scope captures, you can see that when natively outputting separate HV sync, the dreamcast syncs are quite "well-behaved" with proper h-sync pulses throughout v-blank

[maxtherabbit]