Quote:
Originally Posted by RufflesRidge
Have you confirmed that changing this setting actually changes the port behavior? If they removed it from the API I assume it was for a reason.
|
Yes, we have confirmed it. We ran our LPD-8806 lights off of them and they worked perfectly. The LPD-8806 lights are 8 bits per word and the WPILib API seems to only provides 7 bits per word. With the spidev, we were able to change the output to 8 bits per word.
The old SPI class from the WPI library wasn't actually SPI. On the CRio it would bit bang the Digital IO ports to act like SPI. The problem with that is the software had to take resources away from other tasks to emulate SPI. The RoboRio has dedicated hardware for SPI so it doesn't need to take away valuable resources from the rest of the robot. I don't know why they didn't put in the bits per word setting into the new SPI class. The only reason I can think of is that a lot of IC's use 7 bits per word. But that doesn't explain why they wouldn't give us the option to change it.