Comtrol AT Commands - Manual (Page 145)

AT Commands for CX81801/CX06833/CX81300/CX06827 Modems Reference Manual
102184B Conexant 3-119
S86 - Call Failure Reason Code
When the modem issues a NO CARRIER result code, a value is written to S86 Register
to help determine the reason for the failed connection. S86 records the first event that
contributes to a NO CARRIER message. The code definitions are:
Range: 0-26
Default: 21
S86=0 Normal hangup, no error occurred.
S86=1 Reserved.
S86=2 Reserved.
S86=3 Call Waiting caused disconnect.
S86=4 Physical carrier loss.
S86=5 No error correction at the other end.
S86=6 No response to feature negotiation.
S86=7 This modem is async only; the other modem is sync only.
S86=8 No framing technique in common.
S86=9 No protocol in common.
S86=10 Bad response to feature negotiation.
S86=11 No sync information from the remote modem.
S86=12 Normal hangup initiated by the remote modem.
S86=13 Retransmission limit reached.
S86=14 Protocol violation occurred.
S86=15 Lost DTR.
S86=16 Received GSTN cleardown.
S86=17 Inactivity timeout.
S86=18 Speed not supported.
S86=19 Long space disconnect.
S86=20 Key abort disconnect.
S86=21 Clears previous disconnect reason.
S86=22 No connection established.
S86=23 Disconnect after three retrains.
S86=24 Call Waiting tone detected.
S86=25 Extension pickup detected.
S86=26 Remote hangup detected.