Rockwell Automation 1746-HSTP1 Stepper Controller Module/ User Manual - Manual (Page 46)

Publication 999-121 - December 1999
Configuration and Programming 5-11
Notes:
1. A 0 to 1 transition of the above control bits must occur to cause
the associated operation to take place.
2. Reaching either the CW or CCW limit switch during a normal
move or jog operation is treated in the same manner as a pulse
train enable/disable input. That is, the motor stops and the
current position becomes invalid. The “one shot jog” feature
defined in the Jog Commands, later in the chapter, must then be
used to move the motor away from the limit switch.
3. The data format of output words 1-7 is decimal.
4. Most significant words (MSW) contain the 1000s places (the
upper four digits) of the velocity and position data. The least
significant word (LSW) contains the 1s, 10s and 100s places (the
lower three digits).
5. A negative position value is indicated by setting the most
significant bit in output word 2.
6. The position parameter has a range of
±8,388,607.
7. The velocity parameter has a range of starting speed
≤ velocity ≤
250,000.
8. The acceleration and deceleration parameters have a range of 1
≤ acceleration/deceleration ≤ 2000 and is measured in pulses
per millisecond per second.
Absolute/relative move commands
Set bit 0 to command an absolute move. Set bit 1 to command a
relative move. Bit 15, the most significant bit of command mode
output word 2 (msw position), can be used to denote a ccw move. A
1 produces a ccw move, while a 0 produces a cw move. Note that
CCW and CW refer to direction of stepper motor rotation.
The current position of the axis must be valid in order to perform an
absolute move, but not to perform a relative move. The current
position is not valid following a “power-up” or a configuration
operation.
IMPORTANT
A home operation or a preset must be performed to
validate the current position.