DTL_RMW parameters

name_id

is the handle of the solicited data item to be read. Handles were assigned by RSLinx Classic software when solicited data items were defined with the DTL_C_DEFINE function.

variable

is a pointer to a buffer in the client application into which the specified data item will be written.

and_mask

is a mask value that is applied to the data item by performing a bit-wise AND of the original data with the mask value.

or_mask

is a mask value that is applied to the data item by doing a bit-wise OR of the data with the mask value. The OR mask is applied to the data after the AND mask.

io_stat

is a pointer to a buffer in the client application into which the final I/O completion status will be written.

wait_id

is the wait identifier number assigned to a particular asynchronous, solicited, read/write function. Valid values range from 1 through 40.

timeout

is the maximum time (in milliseconds) that the client application will wait for this function call to complete. If the call does not complete before the specified time expires, control will be returned to the client application and the final I/O completion status will be set to DTL_E_TIME.

A timeout value of DTL_FOREVER (defined in Dtl.h) specifies that this function should not return until at least one of the expected wait identifiers becomes set. If one of these wait identifiers never becomes set, the I/O operation will never complete unless a response is received from the network interface.

callback_proc

is a routine in the client application that will be called by RSLinx Classic software after an I/O operation completes or times out. For detailed information, see the DTL_IO_CALLBACK_PROC function.

callback_param

is an uninterpreted value that will be passed into callback_proc when the I/O operation completes. The client application may use this value as an index, pointer, or handle for processing a reply. For detailed information, see the DTL_IO_CALLBACK_PROC function.