Maxim Integrated 73M1866B/73M1966B Reference Driver - Manual (Page 45)

UG_1x66B_015 73M1866B/73M1966B Reference Driver User Guide
Rev. 2.7 45
6.3 FXO Hook Switch Control Services
The configuration and control of the FXO Hook Switch is accomplished by using the IOCTLs summarized
in Table 3.
Table 3: FXO Hook Switch Control Services
Events and Status Description Descriptor
M1966B_ENNOM_DELAY_TIMER Allows the developer to tune the EnNom response
timer. Channel
M1966_ATH1 Issue off-hook in the FXO interface. Channel
M1966_ATH0 Issue on-hook in the FXO interface. Channel
M1966_ATDP Pulse dial. Channel
M1966_ATDP_CANCEL Pulse dial abort or cancel. Channel
M1966_ATDP_PARAM Pulse dial parameters. Channel
M1966_FLSH_CFG Configure of flash-hook parameter for the FXO
interface. Channel
M1966_FLSH_SET Perform hook flashing on the FXO interface. Channel
M1966_SEND_WETTING_PULSE Perform a wetting pulse on the FXO interface. Channel
6.3.1 M1966_ENNOM_DELAY_TIMER
This IOCTL allows an application program to change the ENNOM delay timer from the default value of
350 ms to any value within the valid ranges of 10 to 350 ms, inclusive
Description
Delaying of ENNOM bit setting is required for loop stabilization during off hook operation. However, the
duration depends largely on the quality of the hook circuit design. The driver uses the default setting of
350 ms an optimized choice for response time and voice quality. This IOCTL allows developers to tune
this timing value to suit their specific needs.
#define M1966_ENNOM_DELAY_TIMER _IOWR(0xA4, 0xF8, unsigned int)
Prototype
int ioctl (
int chan_fd,
int M1966_ENNOM_DELAY_TIMER,
unsigned long param );
Parameters
Data Type Name Description
int chan_fd Channel descriptor.
int M1966_ENNOM_DELAY_TIMER I/O control identifier for this operation.
unsigned long param The desired ENNOM delay duration.
Range from 10 to 350 ms, inclusive.
Return Values
Data Type Description
int Always returns 0.