9 miscellaneous, Miscellaneous, M1x22_threshold_override – Maxim Integrated 73M1822/73M1922 Control Module User Manual
Page 56
 
73M1822/73M1922 Control Module User Guide
UG_1x22_053
56
Rev. 1.0
6.9 Miscellaneous
6.9.1 M1X22_THRESHOLD_OVERRIDE
Description
Various modem channel parameters are conveniently grouped and predefined in the country parameter 
setting as specified in 
Section 7.2
. These parameters are programmed during channel initialization ioctl
(M1X22_CH_INIT). However, these parameters can be overridden at runtime to fine tune to the desired 
threshold for the specific installation using this M1X22_THRESHOLD_OVERRIDE IOCTL. 
 
Note: This IOCTL must be invoked after M1X22_CH_INIT to prevent the parameter from over written by 
M1X22_CH_INIT
 
#define M1X22_THRESHOLD_OVERRIDE _IOWR(0xA4,0xB3,unsigned int) 
 
Prototype 
int ioctl ( 
 
int chan_fd,
int M1X22_THRESHOLD_OVERRIDE,
unsigned long param );
 
Parameters 
Data Type
Name
Description
int
chan_fd
Channel descriptor.
int
M1X22_THRESHOLD_OVERRIDE I/O control identifier for this operation.
unsigned long
param
Pointer to the M1X22_THRESH_OVERRIDE_t 
structure. 
 
Return Values 
Data Type
Description
int
-EFAULT – Failed to perform threshold override. 
0 – Successful.