Honeywell UDC2800 - Register Address Structures

Configuration ID Tags
Function codes 20 and 21 use the RS485 tag IDs for accessing
configuration and process-related data. These tags are fully
explained in Section Modbus Read, Write and Override Parameters.
The tag IDs represent the register addresses used in the Request
Message.
Register Address Structure
Table 11-2: Integer Parameter Type
Register Numbers
(Dec)
Name Access Notes
1 Type = 1 NOT
SUPPORTED
16-bit Unsigned
Integer
2 Attribute NOT
SUPPORTED
1 = Read Only,
2 = Read/Write
3 Value (16 bit integer) Read / Write
4 Not Used NOT
SUPPORTED
5 Low Range (16 bit
integer)
NOT
SUPPORTED
6 Not Used NOT
SUPPORTED
7 High Range (16 bit
Integer)
NOT
SUPPORTED
8 Not Used NOT
SUPPORTED
9 to 13 Description Text (ASCII
string)
NOT
SUPPORTED
Table 11-3: Floating Point Parameter Type
Register Numbers
(Dec)
Name Access Notes
1 Type = 2 NOT IEEE Floating
315
Chapter 11 - Modbus RTU Function Codes 20&21