Rockwell Automation DAG6.5.8 APPLICATION GUIDE SCADA SYSTEM - Manual (Page 119)

Publication AG-UM008C-EN-P - February 2005
Configuring MicroLogix 1100/1200/1500 Controllers 3-51
4. Enter the data table size and type for each required file. The data
table file(s) (not including the five additional tables if Expanded
is checked) will be created automatically.
When the system driver is Modbus RTU Slave, you can change the
following communication port parameters as listed below.
Modbus Slave Memory Map
The Modbus memory map is summarized in the table above and
detailed in the table on the next page.
Parameter Options Programming
Software Default
Channel MicroLogix 1200: Channel 0
MicroLogix 1100: Channel 0
MicroLogix 1500 1764-LSP Series B and higher: Channel 0 and 1
MicroLogix 1500 1764-LRP: Channel 0
0 (1200, 1100 &
LSP)
1 (LRP)
Driver Modbus RTU Slave
Baud Rate 300, 600, 1200, 2400, 4800, 9600, 19.2K, 38.4K 19.2K
Parity none, even, odd none
Node Address 1 to 247 decimal 1
Control Line No Handshaking, Half-Duplex Modem (RTS/CTS Handshaking) No Handshaking
Inter-character
Timeout (x1 ms) 0 to 65535 (can be set in 1 ms increments); 0 = 3.5 character times
Specifies the minimum delay between characters that indicates the end of a message packet.
0
Modbus Data Table
File Number
Assignment
(Must be Binary or
Integer file type)
Coils (Discrete outputs, Modbus addresses 0001 to 4096) range = 3 to 255, 0 = no file 0
Contacts (Discrete inputs, Modbus addresses 10001 to 14096) range = 3 to 255, 0 = no file 0
Input Registers (Read Only, Modbus addresses 30001 to 30256) range = 3 to 255, 0 = no file 0
Holding Registers (Read/Write, Modbus addresses 40001 to 40256) range = 3 to 255, 0 = no
file 0
RTS Off Delay
(x20 ms)
0 to 65535 (can be set in 20 ms increments)
Specifies the delay time between when the last serial character is sent to the modem and
when RTS is deactivated. Gives the modem extra time to transmit the last character of a
packet.
0
RTS Send Delay
(x20 ms)
0 to 65535 (can be set in 20 ms increments)
Specifies the time delay between setting RTS until checking for the CTS response. For use
with modems that are not ready to respond with CTS immediately upon receipt of RTS.
0
Pre Transmit Delay
(x1 ms)
0 to 65535 (can be set in 1 ms increments)
When the Control Line is set to No Handshaking, this is the delay time before transmission.
Required for 1761-NET-AIC physical Half-Duplex networks. The 1761-NET-AIC needs 2 ms of
delay time to change from receive to transmit mode.
When the Control Line is set to Half-Duplex Modem, this is the minimum time delay between
receiving the last character of a packet and the RTS assertion.
0