cCall [pPortSetReadCallback], <hPort, RxTrigger, \ <OFFSET32 CommNotifyProc>, lReferenceData> or eax, eax jz error_handler
Called by the _VCOMM_SetReadCallback service to set the notification threshold for the receive queue and register a callback function for receive-queue threshold notification.
hPort
Address of a _PORTINFORMATION structure returned by the PortOpen function.
RxTrigger
Receive-queue notification threshold. When the number of bytes in the receive queue reaches this value, the port driver calls the function specified by CommNotifyProc. Can be –1 to disable receive-queue notification.
CommNotifyProc
Address of the callback function for receive-queue notification. Can be different from the notification function for event notification and transmit-queue notification. For more information, see the CommNotifyProc function.
lReferenceData
A client-defined 32-bit value that is passed to the callback function. Can be different from the reference data specified for event notification and transmit-queue notification.
See also CommNotifyProc, _PORTINFORMATION, PortOpen, _VCOMM_SetReadCallback