Sierra Wireless MP 700 Series, Command Reference Manual

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MP 700 Series GPS AT Command Reference
• Quiet off (
Q0
) enables the modem to issue result codes
following commands. Quiet on (
Q1
) suppresses result
codes entirely; responses remain unaffected.
• Verbose result codes enabled (
V1
) provides results in
English text appended with
<CR><LF>
. Verbose off (
V0
)
returns the results as ASCII numeral codes. Numeric codes
are much easier to process using software.
With Echo on (
E1
- the default) data received from the local
host while in command state is echoed back to the host. This
can present problems to machine control, which is not inter­
ested in an echo of its own commands to the modem. In some
configurations the echo should be turned off (
E0
).
Response and Result Framing
Depending on the modem configuration, modem responses
and result codes are framed, typically with the
<CR>
and
<LF>
characters.
If you are designing or customizing software that will interface
with the modem using AT commands, it is necessary to under­
stand how the modem frames its responses and result codes.
Framing Characters The modem frames its replies with
carriage return and line feed characters as they are defined in
registers
S3
and
S4
respectively. These are normally the ASCII
value 13 for carriage return (
<CR>)
and 10 for line feed (
<LF>)
.
(The following discussion assumes that
<CR>
and
<LF>
are
used.)
Response framing
Regardless of how the modem is configured, responses to
commands are in the form of ASCII text with a trailing
<CR><LF>
. Where a response has more than one line, each line
is terminated with a
<CR><LF>
.
When the Verbose setting is on (
ATV1
, see page 102) each
response has a leading
<CR><LF>
. If Verbose is off (
ATV0
),
there are no leading characters prior to the first line of
response.
The setting of Quiet (
ATQ
, see page 102) has no impact on
responses.
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