Emerson PACSystems RSTi-EP - Supported Modules and Power Supplies

User Manual Section 4
GFK-2958L May 2021
Detailed Descriptions of the Fieldbus Network Adapters 104
Implemented Modbus Functions
Function
code no.
Function
Description
1
Read Coils
Reading of output bits in the range of 0x0800 –
0x09FF†
2
Read Discrete Inputs
Reading of input bits in the range of 0x0000 – 0x01FF†
3
Read Holding Registers
Reading of multiple holding registers
4
Read Input Registers
Reading of multiple input registers
5
Write Single Coil
Writing of an individual output bit in the range of
0x0800 – 0x09FF†
6
Write Single Registers
Writing of individual holding registers
15
Write Multiple Coils
Writing of output bits in the range of 0x0800 – 0x09FF†
16
Write Multiple Registers
Writing of multiple holding registers
22
Mask Write Register
Bitwise changing of one holding register
23
Read/Write Multiple
Registers
Reading of multiple input registers and writing of
multiple holding registers simultaneously
†
Function codes 1, 2, 5 and 15 for bit-wise access to registers. For the usage of these codes please note:
In MODBUS protocol bit addressing separated from register addressing has not been specified. Bit and
register address need to be implemented within the access address as follows: dismiss the most
significant digit of the register address, shift the three less significant digits to the left and use the vacant
least significant digit for bit addressing.
Example: register access with function code 1 to address 0x80AB would be a read access to register
0x080A bit 11. Therefore, the usage of function codes 1, 2, 5, 15 is limited to the address range of
0x0000 – 0x01FF and 0x0800 – 0x09FF.
4.4.6 Supported Modules and Power Supplies
The following modules can be used with the current release of the RSTi-EP Modbus Network
Adaptor:
Part Number
Module Description
Digital Input Modules
EP-1214
Digital Input, 4 Points, Positive Logic 24Vdc, 2-, 3-, or 4-Wire
EP-1218
Digital Input, 8 Points, Positive Logic, 24Vdc 2-Wire
EP-1318
Digital Input, 8 Points, Positive Logic, 24Vdc 3-Wire
EP-125F
Digital Input, 16 Points, Positive Logic, 24Vdc, 1-Wire
EP-12F4
Digital Input, 4 Points, Positive Logic 24Vdc, 2-, 3-, or 4-Wire, Time stamp
EP-153F
Digital Input, 16 Points, Negative Logic, 24Vdc, 1-Wire
EP-1804
Digital Input, 4 Points 110/230Vac (65 – 277Vac), 2-Wire, Isolated
Digital Output Modules
EP-2214
Digital Output, 4 Points, Positive Logic 24Vdc, 0.5A, 2-, 3-, or 4-Wire
EP-2614
Digital Output, 4 Points, Positive Logic 24Vdc, 2.0A, 2-, 3-, or 4-Wire
EP-2634
Digital Output, 4 Points, Positive/Negative Logic 24Vdc, 2.0A, 2-, 3-, or 4-Wire