Wait_Recal ($F192)

Wait for t2 (the refresh timer) to timeout, then restart it using the value in $C83D. then, recalibrate the vector generators to the origin (0,0). This routine MUST be called once every refresh cycle, or your vectors will get out of whack. This routine calls Reset0Ref, so the integrators are left in zero mode.

 

EXIT:

DP = $D0

D-reg, X-reg trashed

 

Source