Rockwell Automation 1771-QA Stepper Positioning Assembly User Manual - Manual (Page 34)

3–12 Programming and Operation
Publication 1771-UM002A–EN–P – May 2000
The load jog command bit (bit 03 of the single move control word,
defined in section titled “Move Block”) must be set to identify jog
move block data.
The user program should clear the software jog reverse command bit
and allow the stepper controller module time to see the bit cleared
before another jog to that axis is enabled.
Bit 15 Software Jog Forward Command Bit.
Same as bit 14. See software jog reverse command bit.
Bit 16 Moveset Bit.
Successive movesets can be programmed for continuous execution
using the moveset bit. This bit can be used to label each block
transfer of move data as moveset 0 or moveset 1. When movesets
are alternately labeled 1 for the first, 0 for the second, 1 for the third,
etc., user program logic can sequence the movesets without
interruption as if they were one large moveset. The number of
successive movesets is limited only by processor memory.
Once a positioning profile has begun, none of the moves of the
working moveset can be updated. However, the storage moveset in
the stepper controller module can be updated provided that the
moveset bit in the transferred (updated) moveset has the same setting
(0 or 1) as the storage moveset bit. Refer to section titled
“Movesets.”
In large systems or systems using remote I/O, moveset timing will
depend upon block transfer timing. Refer to “Handshaking,” page
3–35, for more information.
Bit 17 Override Command Bit.
The override bit is set in the moveset containing the override data.
When the override command is enabled, the override bit causes the
current moveset to be interrupted and the override moveset to be
blended immediately. The first move of the override moveset is
blended with the interrupted move in progress. Refer to section
titled “Override Ramp Time Considerations” to ensure that the first
move of the override moveset will be compatible with any worst
case move in progress.
Generally, bits of the moveset control word are set by user program
logic. A command to the stepper controller module should be
cleared and the stepper controller module allowed sufficient time to
see the bit cleared before the next command is transferred. See the
section titled “Handshaking.”