Re: Does the PD board Output 12v Stable?
 

Also, I'm having a hard time imagining what you could possibly want from a secondary computer on board. The PowerPC processor in the cRIO is the most powerful CPU we've ever had at our disposal, by a factor of like 100. If it can't do what you're trying to do with an off-cRIO processor, I'd be surprised.

Re: Does the PD board Output 12v Stable?
 

The 12V supply is only capable of 20 watts. Therefore, you can't do this, regardless of the rules.

I am interested in what you are trying to accomplish. We might be able to help you find a better way.

Re: Does the PD board Output 12v Stable?
 

In theory, one could connect a coprocessor to the control system via I2C and use the coprocessor to provide serial communication with some sensor. It would be a rather sneaky way to get around FIRST banning use of the serial port on the cRIO, but would be technically legal.

Re: Does the PD board Output 12v Stable?
 

I suppose, though IMO, its alot of added electronics and stuff to talk to some sensor, and if it requires that kind of nonsense to talk to it, its probably more complicated of a sensor than you really require.

Re: Does the PD board Output 12v Stable?
 

We are aware of this; we will wire the serial port to the gpio of a digital sidecar.

Our robot design has forced us to become something of a sniper - we should have the accuracy, and want additional speed in processing images. We may use a second camera to help with targeting.
The fact tha the old processor was 1/100th of the current one doesn't mean the new one is blazing fast, it means the old one was very slow. ;)
I don't view ~450 mhz as very fast, particularly when we can only get image processing (at the lowest possible resolution) to run at about 20 fps, with nearly no other operations running simultaneously.

Do you mean 20 amps?
Watts = Amps x Voltage
20 = Amps x 12
Amps = 20/12 = 1.67

I'm pretty certain that the motors draw more than that.



-jonathan

Re: Does the PD board Output 12v Stable?
 

No, he means the regulated 12V output can only support up to 20 watts; which is enough for the wireless bridge. The other power distribution outputs are limited by the circuit breakers (20, 30, 40 Amps.)

Re: Does the PD board Output 12v Stable?
 

Errr... How is the regulated power supply relevant?


-jonathan

Re: Does the PD board Output 12v Stable?
 

You wanted a clean 12V supply for your custom electrics. The only clean 12V supply is provided by the regulated 12V output for the wireless bridge. Eric mentioned that for your application the regulated 12V supply does not offer the 90 Watts you need; only 20 Watts, and it's also by rule exclusively for the wireless bridge.

In the end, if you want a regulated (clean) 12V supply you will have to provide it yourself by attaching to the unregulated outputs (the ones with circuit breakers you add in yourself.)

Re: Does the PD board Output 12v Stable?
 

The question was meant to address how regular the power was when taken from the unregulated outputs - I'm not planning to plug the wireless bridge into the unregulated power supply, even if it's regulated power would have supplied a high enough wattage to power the motherboard. The main point of the question was to determine how variable the current/voltage was when taken directly from the unregulated supply. Thx everyone for fully answering the question :)

-jonathan

Re: Does the PD board Output 12v Stable?
 

If the voltage vs time graph were a road, and you were to drive on it, you would lose your lunch. It is a very dirty, very bouncy thing.

Re: Does the PD board Output 12v Stable?
 

Your Rover Wheels would be completely shredded ;)

Russ