AquaMan wrote:"The answer to half of my question ended up being "PIC processor" which I can get for $1 then try to write my own firmware, or buy a pre-programed one for USB for $5.

So you're all set? Got all the help you need? (For now at least )

Guys, I'm pretty sure the OP doesn't care about other, simpler ways to drive the motors, he/she wants to learn about using a USB connection for physical computing. Hence the title being 'USB instead of GPIO' That's why I showed him my Uno option that uses USB :D Yeah, I was mainly talking about som...

Guys, I'm pretty sure the OP doesn't care about other, simpler ways to drive the motors, he/she wants to learn about using a USB connection for physical computing. Hence the title being 'USB instead of GPIO'

Firstly, why do you want to program it on your main computer? And how would you simply 'send it over?' I think it's much easier to just program right on the Pi, to greatly simplify debuging. How I do it (not sure if this is 'normal' so to speak) is to log in as Root and then just write it in Idle. I...

I'm nearly certain that DeSmuME runs on the pi, so you could simply open terminal and type Also, what emulator were you using on your main computer if not DeSmuME?

I've never messed around with using the wires in a USB before, but regarding your final question: What is between the mini-usb plug and the GPIO pins? There is a small microcontroller between that reads/replies to the serial data the USB cable is giving it, and then uses that data to turn on/off the...

The GPIO pins can be configured as inputs which allow you detect what you input to them is either high or low (but the input should not go outside the 0V-3.3V range else you'll probably damage he chip), or configured as outputs which can be switched high (~3.3V) or low (~0V). The circuit diagram yo...

joan wrote:You can't control the power rails. They are on as long as the Pi is switched on.

Sorry, I meant how can I open/close the circuit. Can the GPIO inputs act as a ground that can be turned on and off? Or do they only test for an input?

If you try and take too much current they will overheat and blow up and may take other parts of the processor with them (=dead Raspberry Pi). You need some circuitry designed to drive relays between the GPIO pin and the relay. I was looking into buying these relays: http://www.sainsmart.com/arduino...

On the Pi there are gpios and there are power rails and there are ground rails. A power rail such as the 3.3V and 5V pins are nothing to do with the gpios. You may well damage the gpios if you try to drive relays or motors directly from them. So I should have the positive line coming from one of th...

I've started building a remote-controlled car. I have a couple of relays with a 5v coil that I'm using. (The motors run off of 9v) I tested the relays on the 3.3v pins in the GPIO header, and they worked! So I thought that I didn't need to buy any level shifters or anything. However, when I tried it...

Looking at it , mahjonggs suggestion makes a lot more sense than mine. And i believe he refers to using a simple off-the-shelf relay to switch between the two signals , nothing specific for RCA/Composite. ghans Thanks. Now that you say that, my question seems a bit dumb :D Also, thanks for the tips...

use a relay to switch between the external composite signal, or the PI's, other solutions will be massively more complex. Do you mean a composite, RCA relay? (a relay that switched between different composite signals?) Or some kind of homemade motor-switch to physically move a wire to open/close a ...

Hi, I want to set up a (simple?) project of either displaying the Raspberry Pi's desktop, or an RCA video signal. I would toggle it with a button/switch, not sure yet, but the main problem is how to get the RCA video into the Pi, and then displaying it. Do I need some kind of USB adapter? Or can I u...