
4–15Communications Overview
Publication 2711-6.0
Transferring Multiple Blocks
Multiple block transfers use a single channel (single Module Control
and Status Bytes defined). Each block transfer read or write must be
a unique length since the PanelView terminal uses the block size to
determine the starting location of the read or write. The following
example illustrates a block transfer write of two blocks.
BTW
(EN)
BLOCK TRANSFER WRITE
Rack 03
Group 0
Module 0
Control Block N16:6
Data File N90:10
Length 60
Continuous N
➀
The PLC ladder logic program initiates multiple block
transfers of 2 data blocks (7 words and 60 words).
➁ The PanelView terminal receives the first data block and
determines the starting address N7:0 for the write
operation by matching the block size with the address
entered in the Block Transfer dialog.
The PanelView handles the second block in the same
manner.
Data From
PLC
N7:0
N7:1
N7:2
N7:3
N7:4
N7:5
N7:6
N7:7
N7:8
N7:9
➂
The PanelView carries a copy of the logic
controller data tables N7:0 to N7:6.
BTW
(EN)
BLOCK TRANSFER WRITE
Rack 03
Group 0
Module 0
Control Block N16:1
Data File N7:0
Length 7
Continuous N
Data From
PLC
➄ The PanelView screen objects are updated
using the new data.
Block 1 Transfer N90:8
N90:9
N90:10
N90:11
➃
The PanelView carries a copy of the logic
controller data tables N90:10 to N90:69.
Block 2 Transfer
. . .
N90:12
N90:67
N90:68
N90:69
N90:70
N90:71
W7N7:0
W
60
N90:10
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