Rockwell Automation 1758-RTU202 DataSite Software User Manual FRN 1.2 - Manual (Page 268)

Publication 1758-UM002D-EN-P - October 2010
268 Extension Modbus Protocol for DataSite Controllers (1758-FLO)
Modbus Register Range
The registers used in the DataSite controller include four types of I/O
registers.
Coil registers
Coil registers are single-bit registers located in the digital output section of the
I/O database. There are 4096 coil registers numbered from 00001 to 04096.
State registers
State registers are single registers located in the digital input section of the I/O
database. There are 4096 state registers numbered 10001 to 14096.
Input registers
Input registers are 16-bit registers located in the analog section of the I/O
database. There are 4096 registers numbered 30001 to 34096.
Hold registers
Hold registers are 16-bit registers located in the analog output section of the
I/O database. There are 9999 hold registers numbered 40001 to 49999.
Modbus register range
Type Range Number of
Registers Attribute
Coil Registers 1…4096 4096 RW
State Registers 10001…14096 4096 RO
Input Registers 30001…34096 4096 RO
Hold Registers 40001…49999 9999 RW