Rockwell Automation 57C422B 2 Axis Servo Module - Manual (Page 55)

PROGRAMMING 4-27
must connect the encoder to the proper inputs on the
terminal strip. If you want to gear to the opposite axis
command position, set bit 9 = 1. This option does not require
you to make any external wiring connections. In this mode,
the geared axis will follow all changes to the command
position of the reference axis.
The enable shortest path bit allows the module to determine
the shortest path to take when doing an absolute move in
rotary mode.
No Incremental moves can be performed if this bit is set.
If rotary mode is not selected (in register 0, bits 4 and 12),
setting the enable shortest path bit will cause an illegal
command fault.
The enable automatic backlash compensation bit allows you
to enable automatic backlash compensation as specified in
registers 39 and 40.
The abort self-tuning command is used to abort a self tuning
command. This is the only command that is accepted while
the module is doing a self-tune.
4.35 Register 66: Command
Register 66 is used to command actions from the module.
The bits in this register and in register 67 are mutually
exclusive, i.e., only one function may be selected at a time
from either register. This register is read by the module
continuously. Refer to figure 4.34.