Rockwell Automation 1771-QC , D17716.5.25 SER/B SERVO POS - Manual (Page 142)

Formatting and Interpreting Data Blocks
Chapter 7
7Ć60
During normal operation, the command block is repeatedly transferred to
the 1771-M3 controller. Unless the 1771-M3 controller requests a
moveset block or the parameter block, it requests the command block
(Figure 7.40).
Command block size depends on whether there are one, two, or three
axes. For each axis, the command block contains two control words. It
may also include two position preset words, depending on whether a
position preset is programmed. The following sections describe the
command block words.
Figure 7.40
Command Block Ć Showing Word Assignments
1
2
3
4
1
2
3
4
5
6
7
8
5
6
11
12
Control Word 1 - Axis 3
Word
Word
a) Single-Axis
b) Two-Axis
Control Word 1
Control Word 2
Position Preset (MS) Word
Position Preset (LS) Word
Control Word 1 - Axis 1
Control Word 2- Axis 1
Control Word 1 - Axis 2
Control Word 2 - Axis 2
Position Preset (MS) Word - Axis 1
Position Preset (LS) Word - Axis 1
Position Preset (MS) Word - Axis 2
Position Preset (LS) Word - Axis 2
1
2
3
4
7
8
9
10
Word
c) Three-Axis
Control Word 1 - Axis 1
Control Word 2- Axis 1
Control Word 1 - Axis 2
Control Word 2 - Axis 2
Position Preset (MS) Word - Axis 1
Position Preset (LS) WOrd - Axis 1
Position Preset (MS) Word - Axis 2
Position Preset (LS) Word - Axis 2
Control Word 2 - Axis 3
Position Preset (MS) Word - Axis 3
Position Preset (LS) Word - Axis 3
11815
Command Block