mutterminder Posted July 23, 2017 Share Posted July 23, 2017 I have a Magnavox 8CM515 monitor that I would like to use with a Genesis or SNES. However the analog RGB input has H and V sync while my game consoles have composite sync. Does anybody know if the 8CM515 will work with composite sync? Do I have to make a sync separator? What about the Commodore 1902A? I swear it looks like the same monitor from the back. Quote Link to comment Share on other sites More sharing options...
CatPix Posted July 23, 2017 Share Posted July 23, 2017 (edited) https://www.manualslib.com/manual/1011781/Magnavox-8cm515.html?page=6#manual0 Strange indeed. I would try to send composite sync in on 6 pin DIN, on the vertical signal pin. Can't hurt the circuitry if it doesn't work (analog composite signal is 1v, H&V signals are digital TTL 5V) If the Magnavox doesn't accept that signal, there is a simple chip that convert composite to H&V and vice versa, the LM 1881 : A for the Commodore monitor : http://www.zimmers.net/anonftp/pub/cbm/manuals/monitors/1902A_Monitor_Users_Guide_(English-French).pdf Looks very similar, except that on the 6 pins, it appears to be a Commodore S-video type of input. Edited July 23, 2017 by CatPix Quote Link to comment Share on other sites More sharing options...
mutterminder Posted July 23, 2017 Author Share Posted July 23, 2017 I have some LM1881's but it only has a vertical sync output. You could take the vertical sync and the composite sync and get a horizontal sync with some logic gates but this would introduce some delay. The back of the 1902A does look exactly the same as the 8CM515, so maybe they are the same manufacture, but you're right the 6 pin DIN on the 1902A is Chroma/Luma whereas the same connector on the 8CM515 is analog RGB. However the 8 pin DIN appears to be the same on both. Quote Link to comment Share on other sites More sharing options...
phoenixdownita Posted July 23, 2017 Share Posted July 23, 2017 You can use a more complex sync separator: https://ianstedman.wordpress.com/2016/07/06/synchronise-your-video-engines/ you can try CSYNC for HSYNC on the LM1881 and it could work or use an LMH1980 to just get the sync back. Quote Link to comment Share on other sites More sharing options...
mutterminder Posted July 23, 2017 Author Share Posted July 23, 2017 I've been trying to find some old information on the 8CM515, and in some old TI-99A and CoCo3 newsletters, there is some information which would seem to suggest that the monitor does take composite sync, and it might not even care whether you connect it to H or V sync pin. I'll try making a cable an I'll let you guys know how it comes out. Quote Link to comment Share on other sites More sharing options...
mutterminder Posted July 23, 2017 Author Share Posted July 23, 2017 You can use a more complex sync separator: https://ianstedman.wordpress.com/2016/07/06/synchronise-your-video-engines/ you can try CSYNC for HSYNC on the LM1881 and it could work or use an LMH1980 to just get the sync back. Thanks for the link. There is a lot of good information there. If my simple cable doesn't work, I might give the LMH1980 a try. Quote Link to comment Share on other sites More sharing options...
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