B&B Electronics MODSCAN32 - Manual - Manual (Page 90)

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CreateModbusData (LONG Address, SHORT Size, SHORT *pData)
The CreateModbusData() method exposes user data for access by a
connected modbus master. The supplied Address and Size parameters
define how the data is to be addessed according to the modbus protocol.
The current value of the NodeAddress property determines which slave
node is associated with the defined data.
Address Range Data Type
00000-09999 COIL STATUS
10000-19999 INPUT STATUS
30000-39999 INPUT REGISTERS
40000-49999 HOLDING REGISTERS
CreateModbusData() returns a LONG value which identifies the handle to
the specified block of data. This handle should be maintained by the
controlling application to use as an input parameter to the
DeleteModbusData() method or to identify data which may be written
written from the master. The DataHandle is returned as a parameter with
the DataWrittenFromMaster Event.
DeleteModbusData (LONG DataHandle)
The DeleteModbusData() method removes the specified block of data
from the control. The DataHandle parameter must match the value
returned from a previous CreateModbusData method. Normally, blocks of
data would be created during startup, (Form Load), of an application and
deleted during shutdown. A FALSE return value from DeleteModbusData
signifies that the referenced DataHandle was not contained within the
control.
MessageCounter (LONG InterfaceHandle)
The control maintains a counter of message transactions which occur over
each connection. These counters are accessible by the controlling
application via the MessageCounter() method. The control only
increments the counter for a connection whenever a valid data message is
received from a connected master device.