Rockwell Automation 1771-QB Linear Pos. - Manual (Page 146)

Sample Application Programs
Chapter 10
10Ć2
Figure 10.1
Overview of Block Transfers
PLC
Data Table
Status
Block
Parameter
Block
50100
Block Transfer Read
Setpoint
Block(s)
Motion
Block(s)
1771-QB
Module
Status
Block
Parameter
Block
Setpoint
Block(s)
Motion
Block(s)
Block Transfer Write
Command
Block
Command
Block
To ensure correct block transfer sequence on powerup, it is recommended that
the programs:
make parameter block transfer conditional on the status block’s ready bit
being low
make setpoint block transfer conditional on the status block’s setpoints
received bit for this control loop being low and on the ready bit being high (if
you’re using setpoint blocks)
make the next motion block transfer conditional on the block transfer toggle
bit changing from the state it was in prior to the transfer of the previous block
make command block transfer conditional on the setpoints received bit and
the ready bit both being high
if you aren’t using setpoint blocks, make command block transfer conditional
on just the ready bit being high
Block Transfer Sequencing