Rockwell Automation 1771-QB Linear Pos. - Manual (Page 80)

Chapter
7
7Ć1
Formatting Module Data (WRITES)
Data blocks that you set up in the PLC data table enable you to control the
module from your PLC programs. There are four types of data blocks used in
write operations. The three discussed in this chapter are parameter, setpoint and
command blocks. The motion block is discussed in Chapter 9.
Parameter Block (Required)
The parameter block contains loop configuration information. The module must
receive and acknowledge the parameter block before it can receive setpoint,
motion and command blocks. You will normally only send a parameter block to
the module after reset or powerup. If you do send one during module operation,
the module will not activate the new parameters until axis motion stops.
Setpoint Block (Optional)
By sending a setpoint block, you can specify up to 12 setpoints for each axis.
You can move to a selected setpoint by sending a command block.
Command Block (Required)
By sending a command block, you begin the movement of one axis or both axes
simultaneously. This requires a jog command in manual mode or either a
setpoint or motion segment move command in auto mode.
The parameter block contains parameters to configure the two axes controlled
by the module. Figure 7.1 shows parameter block word assignments.
Data Blocks Used in Write
Operations
Parameter Block