At Modem Emulation Mode; Atv (Response Type) Command; Typical Cni2 "At" Responses - Honeywell CNI2 Operating And Installation Manual

For this discussion the symbol <cr> indicates an ASCII control character called "carriage return"
and is represented by a single value (byte) of 13 decimal or 0D hex.
For this discussion the symbol <lf> indicates an ASCII control character called "line feed" and is
represented by a single value (byte) of 10 decimal or 0A hex.
If the CNI2 will respond to AT modem commands in ALL modes of operation.
If you have a serial device attached to the CNI2's serial port it is likely that the device is
expecting to communicate with an AT-compatible modem. The acronym "AT" means
"attention". AT modem commands always start with the ASCII characters "AT" or "at" followed
by other characters that define specific operations. The final character of a command string is
always a carriage return (<cr>).
Upon completion of a command the modem sends back a response in one of two formats,
either "terse" or "verbose". Terse messages (also called "non-verbose" or "numeric") are often
one to two ASCII numbers followed by a <cr>. Verbose messages are readable ASCII
messages preceded and followed by a <cr><lf> combination. For example when an incoming
call is detected the verbose message will be "<cr><lf>RING<cr><lf>" whereas the terse version
is simply "2<cr>".
These are the typical responses that the CNI will return to the remote device:
Terse
Response
(Note-1)
0
1
2
3 NO CARRIER
4
Note-1: Terse (non-verbose) responses always followed by one carriage return <cr>.
Note-2: Verbose responses always preceded and followed by one carriage return <cr> and one
line feed <lf>.
The remote device may issue commands that were important to the original modem but not to
the CNI2. In these cases the CNI2 will return a standard response such as "OK" to these
commands. Other commands are meaningful and the CNI2 will act upon them. The following is
a list of these commands. The CNI2 defaults to certain settings until programmed otherwise.

ATV (response type) Command

ATV, ATV0: This instructs the CNI2 to return "terse" (non-verbose or numeric) result codes
CNI2 Operating and Installation Guide

AT MODEM EMULATION MODE

Verbose
Response
(Note-2)
OK Accepted, no error
CONNECT Connected with remote modem
RING Incoming call
Connection with remote modem is lost
ERROR Command error

Typical CNI2 "AT" Responses

NOTE
DESCRIPTION
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