[RyanCahoon]

I've actually never heard servo control signals called Pulse Coded Modulation before. Pulse Coded Modulation (according to several webpages found by Google) refers to the process of digitally encoding an analog signal by sampling it at a fixed rate (computer music enthusiasts may recognize the acronym PCM). Maybe there's some relation there, but it's not obvious to me if there is.

Servo signals are usually called Pulse Position Modulated (PPM) signals, which can be considered a special class of pulse-width modulation (PWM) that follows defined timing specifications. The difference in PPM and PWM is PWM usually carries information through the duty cycle (% of the signal period the signal is "high") of the signal, whereas with PPM, the amount of time the signal stays high is the critical factor.

Jaguars accept PPM as input when using "PWM control" (the 3-wire red-black-white/yellow interface) and always use PWM for the power output to the motors. The PPM input is fairly compatible with most servo-control systems, you just have to be careful with the timing. [ErikRantapaa] gave one timing specification; another I've seen is 1ms full reverse, 3ms full forward. You can see where this might lead to problems, i.e. the motor driving one way or another when it's supposed to be stopped. In the case of the difference between the one [ErikRantapaa] specified and the one on the SRS page, it looks like the centers are the same, you just may not have access to the full range of speed/motion. If you're timing is different, you could recalibrate the Jaguars. See the documentation for more details.

--Ryan