Rockwell Automation Allen-Bradley ControlLogix 1756-MVI - Connected Data Transfer

Publication 1756-RM004B-EN-P - October 2000
4-10 CIP Messaging API
Connected Data Transfer
MVIcip_WriteConnected
Syntax:
int MVIcip_WriteConnected(
MVIHANDLE apiHandle,
MVIHANDLE connHandle,
BYTE *dataBuf,
WORD offset,WORD dataSize );
Parameters:
apiHandle handle returned by previous call to MVIcip_Open
connHandle handle of open connection
dataBuf pointer to data to be written
offset offset of byte to begin writing
dataSize number of bytes of data to write
Description:
This function is used by an application to update data being sent on the
open connection specified by
connHandle .
apiHandle must be a valid handle returned from MVIcip_Open.
connHandle must be a handle passed by the connect_proc callback
function.
offset is the offset into the connected data buffer to begin writing.
dataBuf is a pointer to a buffer containing the data to be written.
dataSize is the number of bytes of data to be written.
Note: For Assembly Instance 1, the first 4 bytes of the 5550 input image
table are overwritten with “FF” (hex) when the connection is not open
or broken.
Return Value:
MVI_SUCCESS data was updated successfully
MVI_ERR_NOACCESS
apiHandle does not have access
MVI_ERR_BADPARAM
connHandle or dataSize is invalid
Example:
MVIHANDLE apiHandle;
MVIHANDLE connHandle;
BYTE buffer[128];
// Write 128 bytes to the connected data buffer
MVIcip_WriteConnected(apiHandle, connHandle, buffer, 0, 128 );
See Also: MVIcip_ReadConnected