2 events and status service, Events and status service, M1x22_rng_get – Maxim Integrated 73M1822/73M1922 Control Module User Manual
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UG_1x22_053
73M1822/73M1922 Control Module User Guide
Rev. 1.0
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6.2 Events and Status Service
The driver can be queried for a variety of current status of the modem line via IOCTLs. Table 2
summarizes these services.
Table 2: Modem Line Status Services
Events and Status
Description
Descriptor
Modem line ring status commands.
Channel
Modem line polarity status commands.
Channel
Modem line battery status command.
Channel
Modem line POH status command.
Channel
Event retrieval command.
Device
M1X22_ERROR_CODE_GET Retrieve last error code command.
Device/Channel
6.2.1 M1X22_RNG_GET
Description
Gets the current ring status of the modem line. The current ring status is maintained in the driver internal
variable. This variable is being retrieved by use application using this command.
#define M1X22_RNG_GET _IOWR(0xA4,0xB8,unsigned int)
Prototype
int ioctl (
int chan_fd,
int M1X22_RNG_GET,
unsigned long param );
Parameters
Data Type
Name
Description
int
chan_fd
Channel descriptor.
int
M1X22_RNG_GET
I/O control identifier for this operation.
unsigned long
param
N/A.
Return Values
Data Type
Description
int
The return value can be either of the following:
0 – No ring signal occurred on the modem line.
1 – The modem line is ringing, signaling of incoming call.