7ć38, Formatting module data (writes) chapter 7, Axis control word 2 (words 2 and 9) – Rockwell Automation 1771-QB Linear Pos. User Manual

Page 117: Figure 7.45 axis control word 2

Advertising
background image

Formatting Module Data (WRITES)

Chapter 7

7Ć38

Bits 12 and 13 – Readout Select

Bits 12 and 13 are the readout select bits. The third and fourth status words for
an axis provide either current axis position, following error, or diagnostic
information. The readout select bits determine which information is displayed in
the status block. It is generally set to diagnostics information when using the
extended status information.

Bits 14 and 15 – Control Word ID

Bits 14 and 15 identify the control word of the command block.

Axis Control Word 2 (words 2 and 9)

The structure of the second axis control word is shown in Figure 7.45.

Figure 7.45

Axis Control Word 2

50087

15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

..

.

..

.
...

0, Setpoint (1 to 13), or

0

0

0

0

0

0

0

0

0

Motion segment (14 to 127),

binary format

Bits 0 to 6 – Next Setpoint/Motion Segment

Bits 0 to 6 in the second axis control word contain the number of the next
setpoint or motion segment you wish to initiate. See Chapter 9 for more
information on motion segments.

if all bits are 0 or if the axis is already at the commanded setpoint or motion

segment, the axis remains unchanged.

if the new setpoint/motion segment is in the opposite direction to the

movement of the axis, the axis will stop at the deceleration rate for current
motion before reversing and proceeding to the new setpoint.

the module ignores the setpoint/motion segment until it recognizes a

hardware or software start.

setpoints 1 to 12 are defined in the setpoint block. If you specify setpoint 13,

you must define it in the command block.

Advertising