Omega DP400TP User Manual page 25

Address 255 can be used by the master to communicate with all the connected
equipment (broadcast mode), while with 0 all the devices receive the command,
but no response is expected.
DP400S can introduce a delay (in milliseconds) in response to the master
request. This delay must be set on parameter 129 Serial Delay
Each parameter change is saved by the controller on EEPROM memory (100000
writing cycles).
NB: changes made to Words that are different from those reported in the
following table can lead to malfunction.
Baud-rate
Format
Supported
functions
Looking at the table here below it is possible to find all available addresses and
functions:
RO Read Only
Modbus RTU protocol features
Selection on parameter 127 Baud Rate:
1.200 baud 28.800 baud
2.400 baud 38.400 baud
4.800 baud 57.600 baud
9.600 baud 115.200 baud
19.200 baud
Selection on parameter 128 Serial format:
8, N, 1 (8 bit, no parity, 1 stop)
8, E, 1 (8 bit, even parity, 1 stop)
8, O, 1 (8 bit, odd parity, 1 stop)
8, N, 2 (8 bit, no parity, 2 stop)
8, E, 2(8 bit, even parity, 2 stop)
8, O, 2 (8 bit, odd parity, 2 stop)
WORD READING (max 20 word) (0x03, 0x04)
SINGLE WORD WRITING (0x06)
MULTIPLE WORDS WRITING (max 20 word) (0x10)
R/W Read / Write
.
WO Write Only
User manual - DP400S -
25