Rockwell Automation 1771-QC , D17716.5.25 SER/B SERVO POS - Manual (Page 27)

Positioning with Allen-Bradley PC
Chapter 4
4Ć3
Figure 4.3
A Moveset Block is Sent to the 1771ĆM3 Controller That Sends the Move Blocks Sequentially
to the 1771ĆES Expander
Move 1
Move 2
Move 3
Move 4
Move 21
Moveset block in
the PC Processor
data table
Move 1
Move 2
Move 3
Move 4
Move 21
Moveset register
in the 1771-M3
controller
TwoĆMoveĆBlock
register in the
1771-ES expander
Current
Move
Next Move
Move blocks sent in sequence
as each current move is started.
12007
A complete moveset (21
moves max) is sent in a
single block transfer.
The PC processor sends a complete moveset block to the 1771-M3
controller in a single block transfer. The 1771-M3 controller can hold a
moveset block for each of the three possible axes.
The 1771-ES expander can hold two move blocks, the current move block
available for execution and the next move block. After the current move
is completed and the next move is to be executed, the next move block
becomes the current move block (Figure 4.4).