Campbell CR3000 Micrologger, Operator'S Manual

Page: 479 / 644

Section 8. Operation
479
Syntax
MoveBytes(Dest, DestOffset, Source, SourceOffset, NumBytes)
ReadOnly()
Set a variable to read only.
Syntax
ReadOnly()
8.10.3.2.3 Addressing (ModbusAddr)
Modbus devices have a unique address in each network. Addresses range from 1
to 247. Address 0 is reserved for universal broadcasts. When using a network
of dataloggers in a Modbus over Pakbus configuration, use the same number for
both the Modbus address and the PakBus address.
If a slave is to echo back requests to the master, enter the address of the slave as a
negative number in ModbusMaster().
8.10.3.2.4 Supported Modbus Function Codes
Modbus protocol has many function codes. CR3000 commands support the
following.
Supported Modbus Function Codes
Code Name Description
01 Read coil/port status Reads the on/off status of discrete
output(s) in the ModBusSlave
02
Read input status Reads the on/off status of discrete
input(s) in the ModBusSlave
03 Read holding registers Reads the binary contents of holding
register(s) in the ModBusSlave
04 Read input registers Reads the binary contents of input
register(s) in the ModBusSlave
05
Force single coil/port Forces a single coil/port in the
ModBusSlave to either on or off
06 Write single register Writes a value into a holding register in
the ModBusSlave
15
Force multiple coils/ports Forces multiple coils/ports in the
ModBusSlave to either on or off
16 Write multiple registers Writes values into a series of holding
registers in the ModBusSlave