Specifications

Si2404
Rev. 0.91 53
Reset settings = 0x401E
U77 GEN2
Bit D15D14D13D12D11D10D9D8D7D6D5D4D3D2D1D0
Name IST[3:0] HOI AOC OHT[8:0]
Type R/W R/W R/W R/W
Bit Name Function
15:12 IST[3:0] Intrusion Settling Time (250 ms units).
Delay between when the ISOmodem goes off-hook and the off-hook intrusion algorithm
begins. Default is 1 s.
11 HOI Hang-Up On Intrusion.
0 = ISOmodem will not automatically hang up when an off-hook PPD interrupt occurs.
1 = ISOmodem automatically hangs up on a PPD interrupt. If %Vn commands are set, HOI
also causes the “LINE IN USE” result code upon PPD interrupt.
10 Reserved Read returns zero.
9AOCAuto Overcurrent.
0 = Disable.
1 = Enable.
Note: AOC may falsely detect an overcurrent condition in the presence of line reversals or other
transients. Therefore, this feature should not be used in applications or locations (such as
Japan) where line reversals are common or may be expected.
8:0 OHT[8:0] Off-Hook Time (1 ms units).
Time before LVCS is checked for overcurrent condition after going off-hook (30 ms default).