MAXnet Manual - Pro-Dex, Oregon Micro Systems - #20

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MAX COMMAND REFERENCE MANUAL 1-16 1.6. STEP ENCODER CONTROL COMMANDS 1.6.1. STEP ENCODER CONTROL COMMANDS Stepper systems, like servo systems, use encoder for position feedback. However, stepper systems do not use PID filters due to operating constraints in the stepper motors themselves. Instead, the MAX uses the following commands to perform position maintenance for stepper axes. It is important to note that stepper motor position cannot be maintained over the course of a move but rather at the end of the move. Once the axis has initially stopped, the axis will begin moving again to correct for any error encountered during the course of the full move. This process will continue until the encoder position is within the dead band of the motor's target position. COMMAND PAGE Q = QUERY C=CMD COMMAND DESCRIPTION CL 1-59 C Closed loop control ER 1-82 C Encoder ratio HD 1-94 C Hold deadband HG 1-96 C Hold gain HV 1-102 C Set stepper hold velocity 1.6.2. STEP ENCODER SLIP COMMANDS In applications that require notification when a stepper motor slips beyond a given tolerance, the following commands will be of assistance. These commands do nothing to maintain position. Instead, they tell the MAX to react to a slip condition by notifying the host or ceasing motion. COMMAND PAGE Q = QUERY C=CMD COMMAND DESCRIPTION ES 1-84 C Encoder slip tolerance IS 1-116 C Interrupt on slip RL 1-175 Q Report slip status SK 1-189 C Turn on slip kill mode 1.6.3. ENCODER SLAVE MODES Encoder tracking modes connect a motor to an axis at a given ratio. For each turn of the encoder, the motor will move proportionately. COMMAND PAGE Q = QUERY C=CMD COMMAND DESCRIPTION ET 1-85 C Encoder tracking