New video connector ?

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exxos
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New video connector ?

Post by exxos »

As a thought about how annoying the video connector is solder, and the limited number of pins etc..

I was half wondering if you the motherboard should go with the Falcon style connector instead ? Courses does also mean the problem of sourcing suitable connectors..

We could just simply go with a normal VGA connector. It would give us two more pins, but it looks like this connect as RGB grounds as well, so a normal VGA cable my not simply plug into this thing..

The thought there is as there are 3 grounds, then that is 15 pins - 3 = 12 pins.. So we would actually be one short to match the 13 pin din connector. The option would be to not use separate grounds, but this would mean a standard VGA cable could not be used.. But at least it would be easier connector to obtain and solder cables up for and we could do our own pinout. But still annoying to have a seperate cable than a normal ST one :roll:
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PhilC
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Re: New video connector ?

Post by PhilC »

The VGA cable is marginally better for soldering and of course is universally available, so that would get my vote.
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Re: New video connector ?

Post by Atarian Computing »

I say incorporate UBE into the new STF and use a VGA port and a switch in it's vicinity.
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Re: New video connector ?

Post by PhilC »

Atarian Computing wrote: Fri Sep 21, 2018 4:36 pm I say incorporate UBE into the new STF and use a VGA port and a switch in it's vicinity.
Actually that's a very good idea
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Re: New video connector ?

Post by stephen_usher »

Have you thought about using a DB9, as the CGA standard used.

Surely you only need:
  • R
  • G
  • B
  • VSYNC
  • HSYNC
  • Composite Sync
  • +5V
  • Ground
  • High-res detect
You can use an adapter cable to make up anything else you need. (Sound could be on a separate jack plug.)
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Re: New video connector ?

Post by troed »

Here's exactly what should be done:

_Mux_ Shifter RGB and Mono signals to VGA RGB output. It's up to the user of the board to have a compatible monitor connected. For those with a multisync monitor they'll need no switch, all modes with display.

(This will become even more important with the doubleST and Czietz-trick videomodes)
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Re: New video connector ?

Post by Atarian Computing »

troed wrote: Fri Sep 21, 2018 7:29 pm Here's exactly what should be done:

_Mux_ Shifter RGB and Mono signals to VGA RGB output. It's up to the user of the board to have a compatible monitor connected. For those with a multisync monitor they'll need no switch, all modes with display.

(This will become even more important with the doubleST and Czietz-trick videomodes)
/thread
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Re: New video connector ?

Post by exxos »

troed wrote: Fri Sep 21, 2018 7:29 pm _Mux_ Shifter RGB and Mono signals to VGA RGB output. It's up to the user of the board to have a compatible monitor connected. For those with a multisync monitor they'll need no switch, all modes with display.
That is probably a good idea..

We could multiplex RGB & MONO to the RGB buffers..

I guess it depends how we want to do the switch.. We could just wire it directly to the MONO_DETECT pin to select the multiplexer input.
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Re: New video connector ?

Post by troed »

Yeah I don't know enough electronics for this, but I tried reading up on it a while back and it seemed people claimed you'd need to do it with opamps. Basically always combine the signals. We know it's going to be either/or that's currently of interest, never both at the same time (of course).
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Re: New video connector ?

Post by exxos »

Mux are easy enough. Really just 2 buffers in parallel, just enable one or the other set of buffers. RGB on one set of inputs, MONO on all RGB inputs on the second buffer. I think its basically what the UBE does.
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