This tutorial explains how to terminate a read request. topic.
This tutorial assumes a knowledge of the How to transfer data: Tutorial topic.
An application that must respond quickly can set termination charactes that are expected in the data. The read requests complete if any termination characters appear in the data.
If an application needs to respond quickly to the content of the data that is received, the application can set termination characters. If any termination characters are set, the Serial Communications Server inspects the data during a read request. If the Serial Communications Server detects a termination character during a read request, the Serial Communicatoins Server completes the request with the data.
For example, an application that is reading lines of text can set the termination character to the line end character.
Call RComm::Config()
with
the aConfig
parameter set to the TCommConfig
object.
TCommConfig
object now contains the port settings.
iTerminator
array in the TCommconfig
object
to the terminator characters. The iTerminator
array can contain
four characters. If less than four characters are required, set the characters
from index 0 of the array.
iTerminatorCount
field in the TCommconfig
object
to the number of characters set in the iTerminator
array.
Call RComm::SetConfig()
with
the aConfig
parameter set to the TCommConfig
object.
TCommConfig portSettings; commPort.Config (portSettings); portSettings ().iTerminator[0] = 10; // LF char portSettings ().iTerminatorCount = 1; // so that we terminate a read when each line feed arrives User::LeaveIfError (commPort.SetConfig(portSettings));