Rockwell Automation Allen-Bradley 1769-ASCII, User Manual

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74 Rockwell Automation Publication 1769-UM012B-EN-P - January 2014
Chapter 3 I/O Memory Mapping
Simultaneous Mode
(two channels) Input File In Simultaneous mode, the data is packed in the buffer as follows:
•
Four words of channel 0 header information
•
Channel 0 data of a quantity defined by the Max_Receive_Size parameter
•
Four words of channel 1 header information
•
Channel 1 data of a quantity defined by the Max_Receive_Size parameter
This table illustrates the maximum size allowed.
Table 7 - Simultaneous Mode (two channels) Input File Tag Definitions
Wo
rd
Bit Position
Add-On-Profile Tag
Name Description
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Channel 0 Data
Generic Module Tag Names
0 Tx ID Acknowledged Rx Transaction ID Local:S:I.Ch0TxAck
Local:S:I.Ch0RxID
This is a feedback status of Tx ID most
recently transmitted.
Receive Transaction ID Request. Used
with Ch1RxID for handshake mode.
1 Reserved
(1)
TG0 TS0 ND0 HE0 NR0 RF0 TF0 PA0 RO0 TO0 Local:S:I.Ch0Status See Status Descriptions on page 76 .
2 Firmware Revision, Major Firmware Revision, Minor Firmware not included in the Add-On
Profile.
3 Length (Number of Bytes) Local:S:I.Ch0RxDataLength The amount of data being
transmitted.
4 Character 1 Character 0 Local:S:I.Ch0RxData This defines the receive ASCII
character for the tag.
5 Character 3 Character 2 Local:S:I.Ch0RxData
… Character … Character … Local:S:I.Ch0RxData
x
(2)
Last Character Character … Local:S:I.Ch0RxData
Channel 1 Data
x+1 Tx ID Acknowledged Rx Transaction ID Local:S:I.Ch1TxAck
Local:S:I.Ch1RxID
This is a feedback status of Rx ID
most recently transmitted.
Receive Transaction ID Request.
x+2 Reserved TG1 TS1 ND1 HE1 NR1 RF1 TF1 PA1 RO1 TO1 Local:S:I.Ch1Status See Status Descriptions on page 76 .
x+3 Firmware Revision, Major Firmware Revision, Minor Firmware not included in the Add-On
Profile.
x+4 Length (Number of Bytes) Local:S:I.Ch1RxDataLength The amount of data being
transmitted.
x+5 Character 1 Character 0 Local:S:I.Ch1RxData This defines the receive ASCII
character for the tag.
x+6 Character 3 Character 2 Local:S:I.Ch1RxData
… Character … Character … Local:S:I.Ch1RxData
y
(3)
Last Character Character … Local:S:I.Ch1RxData
(1) Reserved is expected in 1st instance word 0.
(2) X is calculated based on the size of Channel 0 data as specified in the input file. Both channels cannot contain 200 characters as the total configuration file size can be only 108 words.
(3) Y is the connection size minus 1, with a maximum value of 107 for a buffer size of 108.