Rockwell Automation 1758-RTU202 DataSite Software User Manual FRN 1.2 - Manual (Page 325)

Publication 1758-UM002D-EN-P - October 2010
Enron Modbus Protocol for the 1758-FLO DataSite Controller 325
Information Variables This section describes global variables used in the DataSite controller. These
variables contain the information about the controller and can be accessed by
using the Enron Modbus protocol.
Short Integer Variables
Short integer variables are accessed using commands 3, 6, and 16. These
commands are similar to the corresponding standard Modbus commands, and
they use Enron Modbus addressing. The size of the data fields for each
variable is determined by the variable address. The read command returns two
bytes for each requested register. The write command provides two bytes for
each register value. Read-only (RO) registers cannot be written by using
commands 6 and 16.
The following tables list all the short integer variables used by Enron Modbus
in the DataSite controller. The Access column in the tables indicates the
register type. Registers may be read/write (R/W) or read-only (R/O).
Configuration registers are read/write registers.
Firmware and hardware version information
Register Description Access
3001 Firmware version high bytes
(ASCII code range 0x30…0x39 and 0x3E) RO
3002 Firmware version low bytes
(ASCII code range 0x30…0x39 and 0x3E) RO
3003 Hardware version high bytes
(ASCII code range 0x30…0x39 and 0x3E) RO
3004 Hardware version low bytes
(ASCII code range 0x30…0x39 and 0x3E) RO
Real-time clock variables
Register Description Access
3005 Year. Range: 0…99 R/W
3006 Month. Range: 1…12 R/W
3007 Day. Range: 1…31 R/W
3008 Hour. Range: 0…23 R/W
3009 Minute. Range: 0…59 R/W
3010 Second. Range: 0…59 R/W