Possible to manually wire some IO Board functionality direct to the DE-10's GPIO pins?

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CRTified
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Possible to manually wire some IO Board functionality direct to the DE-10's GPIO pins?

Unread post by CRTified »

Context : I intend to connect my DE-10Nano board to an SVGA PC monitor.

Is it possible to manually wire some IO Board functionality direct to the DE-10's GPIO pins, using own basic components?

I am primarily interested in the VGA-out port.

I am accustomed to doing this sort of thing with basic Arduino projects and DIY's, but I need guidance on circuit details.

The reason I ask is that a proper IO Board would cost me a day's income, plus weeks of shipping wait... but I have a soldering iron and wires, donor ports and basic components right here already.

Also, in the DIY principle, if this is relatively-trivially doable, then I would prefer to do it myself anyway. My setup will be buried inside arcade cabinet, I don't need a neat-looking official stack. A simple port pigtailed onto the board is more than fine - IF technically feasible.

But is it???

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Side-question, which may render the above irrelevant :

Is there even any advantage/point of wanting that direct Analog Out, as compared to going the route of a cheap Aliexpress HDMI->VGA adapter??

My assumption was that the more intermediary devices and steps avoided, the better/purer - thus looking at an IO Board-like direct analog out port as the desirable route, as opposed to the HDMI port and converting that to VGA out, but if it's all the same and there are no discernable differences/reasons, then I'll just can this entire thought process...
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Sigismond0
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Re: Possible to manually wire some IO Board functionality direct to the DE-10's GPIO pins?

Unread post by Sigismond0 »

If it's going into an arcade cabinet and you don't need dual output (analog and didgital going to two displays at the same time), direct video is 100% the way to go. In fact, you'll get better quality output than you get on the IO board.

Analog IO board is really only suitable for people that want dual output. And since you won't be able to access the buttons, see the LEDs, or flip the power switch, the digital IO is also pretty useless for you. Save the money!
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Re: Possible to manually wire some IO Board functionality direct to the DE-10's GPIO pins?

Unread post by C-R-T »

It is possible. I did exactly this to get analog audio output together with direct video before I got my analog board in the mail. I just replicated that circuit with through hole components on a small pcb and attached it to the de10 nano with header wires. Worked perfectly.
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Re: Possible to manually wire some IO Board functionality direct to the DE-10's GPIO pins?

Unread post by caad »

Can confirm the Direct Video approach is excellent when putting it in an arcade cabinet.
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Re: Possible to manually wire some IO Board functionality direct to the DE-10's GPIO pins?

Unread post by Antoine.WG »

You can use Direct Video, as others have stated, but you need to be careful with the HDMI-VGA adapter. Not all of them support every mode, especially higher than 1080p or lower than 480p, and at limited refresh rates. Also, most lack an audio out jack and many that have one require separate power, usually USB. Definitely do your homework if you want to go that route. Not all DACs are created equal and you get what you pay for.

Otherwise, the schematics for the v6.1 analog I/O board are a good place to start to recreate it from the GPIO and Arduino pins. Just be aware that you can very easily fry your DE-10 Nano's GPIO and Arduino pins or the entire board if you're not careful. That itself is a darn good reason to consider the analog I/O board (the old version will work fine) or a JAMMA kit if your cabinet can use it.

https://github.com/MiSTer-devel/Hardwar ... rd_6.1.pdf

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