Diagnostic And Test Commands; Ud - Last Call Status Report - Conexant H08-15355F Reference Manual

3.2.9 Diagnostic and Test Commands

3.2.9.1 #UD – Last Call Status Report
#UD is an action command requesting reporting of logged operation events. It does not take parameters and must be the last
command in the command line.
The modem logs aspects of their operation for each call, and saves these results until cleared by one of the following events:
1. Power off
2. Hard reset (e.g., negate DTR with &D3 set; reset button)
3. Soft reset = ATZ or AT&F
4. ATD command issued
5. ATA command issued
6. Automatic answer (e.g., set register S0>0 and ring detected)
These results are NOT cleared by changing DTR, V.24 circuit 108.2, if &D0, &D1 or &D2.
Data Call State Model
For purposes of this command, there are four data call states, and associated status issues:
Call Setup
Calling DCE: get dial tone, generate dial digits, detect call progress signals.
Answering DCE: detect ringing, detect CallerID, etc.
Negotiation
V.25 calling tone/answer tone exchanges
V.8 or V.8bis call function negotiations
V-series modem carrier detection and training
Modem-to-modem protocols (e.g., V.42, V.42bis).
Data Transfer
Bit-error rates, for each direction
Rate renegotiation
Retraining
Call Termination
protocol disconnect signals
carrier disconnect signals
loss of carrier
excessive error rates
1118
Command Reference Manual
Conexant
3-41