© Microhard Systems Inc.
Confidential
56
4.0 Register/Command Reference
4.1 AT Commands
Appendix B is a quick reference for the available AT commands; in this sub-section are details
regarding the most commonly used. To invoke an AT command, enter Command Mode, then
type
AT
<command>
[Enter]
.
A Answer
Upon completion of tasks being done with the modem in Command Mode, invoking this command will
place the modem back ‘online’ (into Data Mode).
If changes were made to
the modem’s
configuration and it is
intended that those
changes be saved to non-
volatile memory, do so
with the AT command
’&W’ prior to placing the
modem online.
g, G Spectrum Analyzer
This is a very useful feature of the P2400. ATg or ATG will provide a display of signal levels received
within the operating environment and frequency range of the modem under test. ATg averages 256
samples, ATG 16,000.
Invoking the ATg command causes the P2400 to sweep the operating band and provide a display of
both the mean and peak signal levels, in dBm, found on each channel.
The ‘graphical’ display is limited from –110dBm to –53dBm, and is in 1dB increments. Ignore the
leftmost asterisk in calculations (as below).
How to interpret the display (example):
...
ch 78 -137dBm *
No signal was measured on channel 78.
ch 80 -105dBm ******...
Mean signal level: -(110-5 (asterisks)) = -105dBm
...
Peak signal level: -(110-5 (asterisks) -3 (dots)) = -102dBm
For the P2400 Channel 1 is at 2401.6 MHz, with subsequent channels in increments dependent on the
link rate. Therefore, to calculate the frequency of channel
n
: (BW = Channel Bandwidth in MHz)
Freq channel
n
= 2401.6+ ((
n-1
) x BW) MHz.
I
n
Identification
The I command returns information about the P2400.
1
Product Code
3
Product Identification (Firmware Version)
4
Firmware Date
5
Firmware Copyright
6
Firmware Time
255
Factory-Configured Options listing
