ST7200 Troubleshooting Guide
Ver. 0.0
Page
3
Network Test
The network test can be verified by the LED behavior. The GSM/cellular LED (Blue)
reflects the state of the GSM registration.
o
Blinking once a second means: Searching for GSM network
o
Blinking every 3 seconds means: GSM lock
You can send the command below to check the GSM registration.
+XT:7050,1
The response is a message string in the format:
$$<UID>,7050,<GSM>,<GPR>,<PDP>,<HD>,<HO>,<PU>,<R>,<%GPS>,<%GPSQ>,
<%GSM>,<%GPR>,<%PDP>,<LV>,<HV>,<CX>,<DBO>,<ABI>,<DBI>,<SO>,<SI>,<
SS>##
<GSM>
is GSM registration state: 0=Not Reg, 1=Home, 2=Search, 3=Denied, 4=Unknown,
5=Roaming
<GPR>
is GPRS registration state: 0=Not Reg, 1=Home, 2=Search, 3=Denied, 4=Unknown,
5=Roaming
<PDP>
is GPRS PDP state, 0=Deactivated, 1=Activated
<%GSM>
is Percent lost GSM
<%GPR>
is Percent lost GPRS
<%PDP>
is Percent lost PDP context activation
If the device cannot register to the network, verify the SIM card and the location to
check for coverage issues. The device will always try to register automatically to the
network.
Output Test
For this test we will need a relay and a multimeter.
Connect PIN 86 and 30 of the relay to a 12V power source and connect PIN 85 to the
ST7200 output (Green wire).
Send the command to set the output to a short circuit
+XT:7005,2,2
You should hear the relay click. With a multimeter check the voltage at pin 87a of the
relay, there should be no current.
Send the command to set the output to an open circuit
+XT:7005,1,2
You should hear the relay click. With a multimeter check the voltage at pin 87a of the
relay, there should be a 12V current.
