Execution of PIDDEF will clear the integrator and differentiator data. There is no command to bypass this. However, if you don't use the built-in PID functions, you may actualy use TBASIC to construct your own PID routine. i.e. storing the P, I and D in DMs and use the variable A to Z to store the result of the I and D term. You can refer to Digital Control books for some algorithm that suit your purpose.