TTL monochrome video output

Store Forums Video Experimenter General Discussion TTL monochrome video output

This topic contains 5 replies, has 4 voices, and was last updated by  Allenwood 2 months, 1 week ago.

Viewing 6 posts - 1 through 6 (of 6 total)
  • Author
    Posts
  • #434

    quarterturn
    Member

    I see the sync chip has H and V sync outputs, and TTL video is otherwise pretty similar to NTSC… so how difficult would it be to use the video experimenter to drive a TTL 15 kHz monitor?

    I have a nice 5″ Kristel TTL monitor from http://www.timeline-inc.com I’d like to use.

    Thank you!

    #876

    Michael
    Keymaster

    I’m afraid I have no experience with TTL video (never heard of it). If the timings are the same as NTSC, then maybe it will work.

    #877

    quarterturn
    Member

    The monitor I have is 15 kHz horizontal scan rate so I guess that’s basically the CGA standard, only in monochrome (640×200). I think that’s also NTSC in non-interlaced mode.

    #893

    quarterturn
    Member

    I think I have found the answer:
    http://www.epanorama.net/documents/vga2rgb/vgamonitor.html

    It describes the LM1881N plus a few log gates to get a true hsync. With that I should be able to drive my TTL monitor using a composite video signal.

    I have a teensy++ 2.0 which has 8k RAM. Timing issues aside, that ought to be good for at least 256×192. That will allow for a 40×24 line display, assuming 5×7 characters with 1 pixel spacing between them.

    #961

    FidelStokes
    Member

    I think that’s also NTSC in non-interlaced mode.

    #10960

    Allenwood
    Participant

    I’m afraid I have no experience with TTL video (never heard of it). If the timings are the same as NTSC, then maybe it will work. HPE6-A48 dumps

Viewing 6 posts - 1 through 6 (of 6 total)

You must be logged in to reply to this topic.