The [PID] instruction in CCW for Micro8xx PIC uses the Dependent Gains form of a PID algorithm. However, the [PID] instruction does not work as advertised. Specifically, the tuning parameter members of the PID_GAINS object used by [PID] are not all consistent the with the canonical/conventional meanings of their names. If pidgains is a tag in CCW of data type PID_GAINS, then its members have the following meanings:
pidgains.Kc - Controller gain, units of dCV/dError
pidgains.Ti - Integral time, units of seconds (s)
pidgains.Td - Factor for calculating a first-order filter time constant, units of seconds-squared (s**2)
pidgains.FC - Derivative time, units of seconds (s)
the product (pidgains.Td * pidgains.FC) is the CV output filter time constant
Note specifically that
the .FC member of PID_GAINS is not the filter constant that the CCW documentation claims it to be;
the .Td member of PID_GAINS is not the derivative time that the CCW documentation claims it to be.