Function Code 02 - Read Input Status; Function Code 03 - Read Holding Registers; Function Code 04 - Read Input Registers; Table 16 Address Ranges Of Function Codes - ABB LVS Digital Manual

F U NCT IO N CO DES
Function codes and their relevant address range are shown in the table below.
Function Codes
FC02
FC04
FC03, 06, 16

Table 16 Address ranges of Function Codes

8.2. Function Code 02 – Read Input Status
This function allows the control system to obtain the ON/OFF status of discrete inputs from
the Digital Gateway. With function code 2 following information can be requested.
• Life Bits
• Status Information
• Control Access Information
• Alarms
• Trips
The valid address range: 10001-19999.
8.3. Function Code 03 – Read Holding Registers
With function code 03, the control system can read the registers that can store the numerical
data, which can be driven to external devices as mentioned below.
• Measuring Values
• Status as Word-oriented bits
• Alarm structure (Warnings/Trips)
The valid address range: 40001-49999
8.4. Function Code 04 – Read Input Registers
Function code 04 obtains the contents of the input registers. These locations receive their
values from devices connected to the I/O structure of field units and can only be referenced,
not altered within the system or via MODBUS as mentioned below.
• Status as Word-oriented bits
• Alarm structure (Warnings/Trips)
The valid address range: 30001-39999
1 TG C90 80 04
Address / Mapping Area
10001-19999
30001-39999
40001-49999
F U NCT IO N CO DE 02 – R EAD INP UT STATU S
Starting Address used in Modbus
Frame
0-9999
0-9999
0-9999
45