Controll over Radio?

[interfect]

Sorry. I guess I didn't make myself clear. Basically, what we want to do is transmit arbitrary bytes from the robot, through the radio link, and out the dashboard port. However, we want to do it on an interrupt basis rather than a loop basis, or as close to an interrupt basis as possible (maybe from the fast user code?). Are the packets sent to the OI constructed by the master uP? Can we hack it to send our own byte stream? If we add stuff to the txdata typedef, tx_data_record, can we trick the master uP into sending it? Or would it just balk? What feilds of that structure are "safe" to set to send arbitrary data? If we made our own structure of the same size, what bytes could we use?

[Noah Kleinberg]

Originally Posted by interfect

Sorry. I guess I didn't make myself clear. Basically, what we want to do is transmit arbitrary bytes from the robot, through the radio link, and out the dashboard port. However, we want to do it on an interrupt basis rather than a loop basis, or as close to an interrupt basis as possible (maybe from the fast user code?). Are the packets sent to the OI constructed by the master uP? Can we hack it to send our own byte stream? If we add stuff to the txdata typedef, tx_data_record, can we trick the master uP into sending it? Or would it just balk? What feilds of that structure are "safe" to set to send arbitrary data? If we made our own structure of the same size, what bytes could we use?

I'm pretty sure that just changing txdata wouldn't do anything, and it's not a good idea to do this for competition purposes anyway. There are a few "user bytes" whose values are sent to the dashboard, which you could use to communicate with it, or you could store values in unused pwm outputs, which are also sent to the dashboard.

[interfect]

How legal is dissassembling the firmware and patching in our own code? That might let us send a bytestream, but is that legal/possible?

[Cuog]

Its possible to flash the master processor with your own data structure code however you will be disabled the entire match.

[interfect]

Originally Posted by Cuog

Its possible to flash the master processor with your own data structure code however you will be disabled the entire match.

Why? Is it part of the rules, or is ti just because the code you flash in dosen't enable the robot like the normal firmware does?

[whytheheckme]

You can use PWM outputs and OI LED outputs and user bytes to send stuff out of the dashboard port.

Take a look at the list of bytes that can be read from the Dashboard port, and see which ones you have control over.

Jacob

[Alan Anderson]

Originally Posted by interfect

How legal is dissassembling the firmware and patching in our own code? That might let us send a bytestream, but is that legal/possible?

For use on a competition robot, messing with the master code is 100% absolutely not legal. It's also not really possible without inside information.

If all you want to do is get back arbitrary bytes from the robot, the existing data stream gives you six "user bytes" for exactly that purpose. You're still restricted to the predefined transmission rate of ~40 packets per second, which I believe is actually maintained by the OI software -- which you have absolutely no control over.