Rockwell Automation Allen-Bradley 1769-ASCII, User Manual

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72 Rockwell Automation Publication 1769-UM012B-EN-P - January 2014
Chapter 3 I/O Memory Mapping
Alternate Mode (one channel
at a time) Output File The alternate mode output file contains the real-time output data from the
module. This table shows the generic module tag definitions on the left. On the
right of the table is the 1769-ASCII module Add-On Profile configuration using
RSLogix 5000 software version 16 and later.
It is assumed that 16 bit words are used. The structure on the left is used with
varying data types; SINT, INT, BOOL and SINT array for data. The Add-On
Profile structures the module output, configuration and input tags differently.
With the Add-On Profile the configuration tags are rearranged as INTs.
The table shows the maximum size of the value and shows the maximum array
size for Alternate Mode.
Table 5 - Alternate Mode (one channel at a time) Output File
W
O
R
D Bit Position
Add-On-Profile Tag
Name
Description
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Generic Module Tag Names
0 Reserved
(1)
Tx Transaction ID Ch0 Local:S:O.Ch0TxID
(2)
Transmit Transaction ID.
1 Reserved Rx Transaction ID Request Ch0 Local:S:O.Ch0RxID
(3)
Receive Transaction ID Request. Used with
Ch1RxID for handshake mode.
2 Reserved Tx Transaction ID Ch1 Local:S:O.Ch1TxID Transmit Transaction ID.
3 Reserved Rx Transaction ID Request Ch1 Local:S:O.Ch1RxID
(4)
Receive Transaction ID Request. Used with
Ch0RxID for handshake mode.
4 Reserved CNI Local:S:O.RxChNumber Channel number of requested input data.
This bit is set by the PLC controller or
other user program to tell the 1769-ASCII
module which data to produce.
This bit is set by the controller based on
the user program; same for all the words
in the Output data file
5 Reserved CNO Local:S:O.TxChNumber Channel number of the output data being
sent. This bit is set by the PLC controller or
other user program to tell the module
which port’s data is being sent to the
1769-ASCII module.
6 Reserved
7 Length (Number of Bytes) Local:S:O.TxDataLength The amount of data being transmitted.
8 Character 1 Character 0 Local:S:O.TxData This defines the transmit ASCII character
for the tag.
9 Character 3 Character 2 Local:S:O.TxData
… Character … Character … Local:S:O.TxData
106 Character 197 Character 196 Local:S:O.TxData
107 Character 199 Character 198 Local:S:O.TxData
(1) Reserved is expected in 1st instance word 0.
(2) Tag name format is `Local:S:O’ where 'S' represents slot number.
(3) Used for handshaking mode.
(4) Used for handshaking mode.