T-Series/Commands/Set Current Position/T-Series Motorized Devices

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Instruction Name Set Current Position
Applies to T-Series motorized devices
Firmware Version 5.xx
Command Number 45
Command Type Setting
Command Data New Position
Reply Data New Position
Safe to retry? Yes
Returns Current Position? Yes
Persistence Volatile
Summary Sets the device internal position counter.

This command override the internal position counter with a new position value specified by the user.

The position data is volatile and will not persist after power-down or reset.

The phase of the stepper motor is controlled by the least significant byte of the position, thus the device may move by +/- 2 full steps unless the new position corresponds to the true current position of the device. This command is useful if you want to turn off the system without losing position. Simply save the position in the controlling computer and turn off the hold current (Command 39) before powering down. After powering up, set the position back to the saved value and turn on the hold current. In this way you can continue without having to home the device. You have to turn off the hold current because when the power first comes on the position will default to the maximum range, and that may be out of phase with the motor's current position. If the hold current is on, it will force the motor into phase with the default position before you've had a chance to restore the current position.

In Firmware 5.21 and 5.22, the new Current Position must be equal or less than Maximum Position. See Set Maximum Position (Cmd 44) for more details on range settings and behaviour.