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I have a strange application where I need to use the VGA output, but with a twist.. The format needs to be 888 instead of the standard 666, AND the VGA sync signals (H-Sync and V-Sync) must be absent. In other words, from the last pixel on the frame to the first pixel on the next frame, there must be no delays. Is this possible? and if so, I would realy appreciate help on getting it running. Thank you..

  • The Pi has no native VGA output. Its analog output is composite. There is an adapter Gert VGA and some rumors about 888 mode... and hello and welcome to Raspberry Pi! Please take the tour and visit the helpcenter to see how things work here. – Ghanima Apr 17 '17 at 19:34
  • I'm pretty baffled as to what you're planning on doing with this. Is it conceivable that you could use an HDMI to VGA converter to get your 8-bit colour, then just use a custom cable out of that with the H- and V-sync lines disconnected? – goobering Apr 17 '17 at 22:59
  • The crux of my requirement is that there be no delay between the last pixel of the previous frame to the first pixel of the next frame. In other words, there must be an un interrupted stream of RGB data. I dont believe the HDMI route would work. – Rudie van Heerden Apr 18 '17 at 9:07
  • @RudievanHeerden even if we talked about solutions not using the hdmi port we wouldn't magically be increasing the rate at which the gpu spits out frames which is what you seem to be looking for, you should try looking into very high hz like 120hz hdmi output on a computer then buy an adapter and do what goobering recommended. But that's just my advice – Mohammad Ali Apr 18 '17 at 21:04
  • @Mohammad Ali. Thank you for taking the time to respond. It is however not my intention to increase the frame rate, but rather, if the pixels were alternately black and white, from the first pixel on the display to the last, one would have a square wave seen on an oscilloscope. This would then be interrupted for the duration of the H-Sync and V-Sync. It is these interruptions I would like to eliminate. – Rudie van Heerden Apr 19 '17 at 9:10

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