Maxim Integrated 73M1822/73M1922 Modem API - Manual (Page 9)

UG_1x22_055 73M1822/73M1922 Modem API User Guide
Rev. 1.0 9
2.3 M1X22_OpenDevice
Description
This API performs the low level opening of the device descriptor. By default, the device descriptor name
is known as “/dev/tsc_1x22_ctl_device”; however, since this is configurable during driver
installation, a different device descriptor name may be used. Refer to driver configuration and installation
more detail. Calling to this open device API is mandatory before any channel descriptor can be opened,
and it must be called after the API Init function.
In addition to opening the device for accessing this API also requires a callback function. This function is
called by the API subsystem to convey the FOX events to the application program. Six parameters are
returned when this callback function is invoked:
eventId : This parameter is the event identification of type M1X22_EVENT_ID.
chanId : This parameter contains the channel ID from which the event is generated.
evtData1: are reserved for special purpose in event handling.
evtData2:
evtData3:
evtData4:
A successful open device returns a non-zero device handle that can be used to access other device
related APIs.
Prototype
M1X22_HANDLE M1X22_OpenDevice (char *devName, void *callback);
Parameters
Data Type Name Description
char * devName Device descriptor name (default: /dev/ter10).
void (*eventCallback)(
M1X22_EVENT_ID eventId,
unsigned int chanId,
unsigned int evtData1,
unsigned int evtData2,
unsigned int evtData3,
unsigned int evtData4) Event status callback function. The parameters
returned by this callback function are event ID,
channel ID and 4 event data that are specific to the
event ID. Most of these event data are not
applicable except those listed in the
“EventCallback Parameters” table below.
EventCallback Parameters
Event Name Parameters
M1X22_EVENT_RING_START evtData1 – Ring burst frequency (in Hz).
M1X22_EVENT_RING_END evtData1 – Ring burst frequency (in Hz).
evtData2 – Ring burst duration (in milliseconds).
M1X22_EVENT_LINE_STATE evtData1 – Channel Hook state (0-on-hook, 1-off-hook).
evtData2 – 0-line current, 1- voltage.
evtData3 – IET index.
evtData4 – Application defined event.
Return Values
Data Type Description
M1X22_HANDLE Non-ZERO value if the device is opened successfully.
ZERO if the device fails to open.