Specifications

29
Example: The table below shows a short string data type with two transmit instances that
are mapped into discrete/M-file Outputs I/O. Each instance is allocated for
three characters (bytes) for serial transmit. The total is ten bytes for the PLC
I/O mapping.
Data
Memory
Table
1514131211109876543210
:
:
O:1.3
O:1.4
Instance 1: Transmit ASCII Character 3
Instance 2: Transmit ASCII Character 1
O:1.5 Instance 2: Transmit ASCII Character 3
O:1.31
::
Output Memory Table of Allen Bradley 1747-SDN DeviceNet Master Scanner Module
O:1.2 Instance 1: Transmit ASCII Character 1 Instance 1: Transmit Data Size (length)
::
O:1.1
Receive (Rx) Acknowledge: bits 0~7
Inst1=bit8, Inst2=bit9, .., Inst8=bit15
O:1.0
1 Word Addressing I/O
1 byte = 8 bits 1 byte = 8 bits
Reserved Read-Only
Transmit (Tx) Toggle: bits 0~7
Inst1=bit0, Inst2=bit1, .., Inst8=bit7
Instance 1: Transmit ASCII Character 2
Instance 2: Transmit Data Size (length)
Instance 2: Transmit ASCII Character 2
Data
Memory
Table
1514131211109876543210
:
:
MO:0.149
::
MO:0.0 Instance 1: Transmit ASCII Character 1 Instance 1: Transmit Data Size (length)
::
MO:0.1
O:1.1
Receive (Rx) Acknowledge: bits 8~15
Inst1=bit8, Inst2=bit9, .., Inst8=bit15
Instance 1: Transmit ASCII Character 2
1 Word Addressing I/O
M-File Output Table of Allen Bradley 1747-SDN DeviceNet Master Scanner Module
1 byte = 8 bits 1 byte = 8 bits
O:1.0
Reserved Read-Only
Inst1=bit0, Inst2=bit1, .., Inst8=bit7
Transmit (Tx) Toggle: bits 8~15
Instance 1: Transmit ASCII Character 3
MO:0.3
Instance 2: Transmit ASCII Character 1 Instance 2: Transmit Data Size (length)
Instance 2: Transmit ASCII Character 2 Instance 2: Transmit ASCII Character 3
MO:0.2