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Unread 06-12-2008, 22:09
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Re: cRIO - motor controller code (esp. victor)

Quote:
Originally Posted by Alan Anderson View Post
That's the root of the problem right there. Why weren't you using a Servo class? The software knows about and exploits the difference between the various output devices. If you lie to it about what you're connecting, you shouldn't be surprised that it doesn't give the results you want.
There is nothing in any documentation that I've read that clearly states that this is the case. The only reason that I ever found out about it is that I observed something through experimentation and dug into the source code to figure out what was going on. For years we've tested basic drive code by watching servo behavior on a benchtop setup. When we tested for the first time with the new system, it didn't seem unreasonable to try the same thing. Now we know, and can deal with it.

I have quickly learned that the new system is not the old system. Things that used to work, no longer do. For example, we used to set all motor output to neutral at the start of every loop for safety, then only set the motors that needed setting. With the new system, as soon as a Set is called, the output is set (which makes sense). When we initially tested, we were getting choppy response. It took a little bit to figure out what was going on, but it's a learning process.