ProSoft Technology MVI56E-LDM - Manual (Page 107)

ControlLogix Platform ♦ "C" Programmable CIP API Functions
Linux Application Development Module Developer's Manual
ProSoft Technology, Inc. Page 101 of 264
March 12, 2014
OCXcip_ReadConnected
Syntax
int OCXcip_ReadConnected(OCXHANDLE apihandle,
OCXHANDLE connHandle,
BYTE *dataBuf,
WORD offset,
WORD dataSize );
Parameters
apihandle handle returned by previous call to OCXcip_Open
connHandle handle of open connection
dataBuf pointer to buffer to receive data
offset offset of byte to begin reading
dataSize number of bytes to read
Description
This function is used by an application to read data being received on the open
connection specified by
connHandle
.
apiHandle
must be a valid handle returned from
OCXcip_Open
.
connHandle
must be
a handle passed by the
connect_proc
callback function.
offset
is the offset into
the connected data buffer to begin reading.
dataBuf
is a pointer to a buffer to
receive the data.
dataSize
is the number of bytes of data to be read.
Notes: When a connection has been established with a ControlLogix controller, the first 4 bytes of
received data are processor status and are automatically set by the controller. The first byte of data
appears at offset 4 in the receive data buffer.
Return Value
OCX_SUCCESS data was read successfully
OCX_ERR_NOACCESS apihandle does not have access
OCX_ERR_BADPARAM connHandle or offset/dataSize is invalid
Example
OCXHANDLE apihandle;
OCXHANDLE connHandle;
BYTE buffer[128];
// Read 128 bytes from the connected data buffer
OCXcip_ReadConnected(handle, connHandle, buffer, 0, 128 );
See Also
OCXcip_WriteConnected