Any GPIO?

[Guest]

I searched the forums and couldn't find an answer.

Does the USB UIRT provide any general purpose IO pins? I'm a DIYer, so I'm not afraid of opening the box and soldering if I have to, but does the firmware and driver support any IO control like this?

I'm looking for a simple way to turn on/off a couple of external LEDs or relays using the UIRT hardware/software. I know I could do this with a parallel port, but I'd like to avoid a cable out the back of the 'puter (the UIRT would be pligged directly into the MB).

Can this be done? If not, is it a planned enhancement? Can it be?

-Tab

[jrhees]

Because the USB-UIRT has some of its roots based in the firmware I developed for the original UIRT2, there *is* some GPIO control. However, the GPIO's are all used for other purposes in the current USB-UIRT. With some effort, 2 of the GPIO's used for zone control as well as 1 GPIO used for the RED indicator LED could be hijacked. The current API and Girder can both control these outputs (Set/Clear/Pulse them).

-Jon

[Guest]

That sounds interesting.

What's 'zone control', exactly? Maybe I could live without that. What are those IOs connected to, physically? Are those the extra emmiter ports?

I assume the 'red indicator' you mention is the LED that indicates IR reception? I think I want to keep that one.

It's good to hear the software supports twiddling these pins already. So to hijack them, I assume I just need to know which pins to disconnect and solder into my own stuff. But how do I prevent the firmware/software from using them for their intended purpose?

-Tab

[jrhees]

I believe if you were to hijack the two Zone control pins you could still operate the SW normally as long as you did not issue Zone-specific transmissions (the Zone control allows the built in IR emitters, and the IR output jack's L and R channels to be individually controlled versus all 3 being enabled by default).

-Jon

[frdfsnlght]

Ok, now I'm properly registered for the forum.

So I take it, I could configure the UIRT to only 'blast' out the front LED and not the rear emitters? Then I could hack the rear emitters and use them as general purpose outputs? Would this require a hardware change, or could I use the outputs directly? Is there a schematic for the UIRT that I could peruse?

Thanks so far.

-Tab

[jrhees]

No, not quite. The 2 GPIOs are part of a gating circuit which controls IR outputs. You would have to remove a couple of internal components and connect to the GPIO's internally. I would give you specific instructions when you were ready.

-Jon

[frdfsnlght]

Ok, I can handle that. I don't actually own a UIRT... yet. I'm in the process of designing my next HTPC (v2 as it were) and I'm trying to get a handle on the all the parts I'll be needing to do what I want. I'll let you know when I need to make the change. Thanks for the help.

-Tab