Rockwell Automation 1785-Lxxx Enhanced and Ethernet PLC-5 Programmable Controllers User Manual
Page 326

Publication 1785-UM012D-EN-P - July 2005
D-26 Instruction Set Quick Reference
Instruction
Description
Block Transfer Read
BTR
If the input conditions go from false to true, a block transfer
read is initiated for the I/O module located at rack 1, group 0,
module 0. The Control Block (BT11:100, 6-word file) contains
status for the transfer. The Data File (N10:110) is where the
data read from the module is stored. The BT Length (40)
identifies the number of words in the transfer. A non-continuous
block transfer is queued and run only once on a false-to-true
rung transition; a continuous block transfer is repeatedly
requeued.
You can also use the N data type for the control blocks.
See page F-8 for a description of prescan operation for
this instruction.
PLC-5/30, -5/40, -5/40E, -5/40L
-5/60, -5/60L, -5/80, -5/80E
controllers
PLC-5/40, -5/40L, -5/60,
-5/60L, -5/80, -5/40E,
-5/80E controllers
PLC-5/60, -5/60L,
-5/80, -5/80E controllers
S:7
bit #
BT queue
full for rack
S:32
bit #
BT queue
full for rack
S:34
bit #
BT queue
full for rack
08
(1)
0
08
10
08
20
09
1
1
09
11
09
21
10
1
2
10
12
10
22
11
1
3
11
13
11
23
12
4
12
14
12
24
13
5
13
15
13
25
14
6
14
16
14
26
15
7
15
17
15
27
(1)
PLC-5/11, -5/20, and 5/20E controllers also
Instruction
Description
Block Transfer Write
BTW
If the input conditions go from false-to-true, the block
transfer write is initiated for the I/O module located at rack
1, group 0, module 0. The Control Block (BT11:0, 6-word file)
contains status for the transfer. The Data File contains the
data to write to the module (N10:10). The BT Length (40)
identifies the number of words in the transfer. A
non-continuous block transfer is queued and run only once
on a false-to-true rung transition; a continuous block
transfer is repeatedly requeued. You can also use the N
data type for the control block.
See page f-8 for a description of prescan operation for this
instruction.
BTR
BLOCK TRANSFER READ
Rack
Module
1
0
0
BT11:100
Group
Control Block
Data File
Continuous
Length
N10:110
Y
40
BTW
BLOCK TRANSFER WRITE
Rack
Module
1
0
0
BT11:0
Group
Control Block
Data File
Continuous
Length
N10:10
Y
40