Gsm/Gps Tracker

[aratti]

Have you correctly placed the label "UM:" in your code?

Al.

[camolas]

Have you correctly placed the label "UM:" in your code?

Al.

Hi ALL,

Its was a small error its solved, I will post the new code using Serin2/out2.
One more time thank you Sir. for hellping and caring.

Xau

[mikebar]

Hi Camolas,
about the signal coverage, what you think about to use:
AT+CSQ

it should tell you how good is the signal.
In the modem I have it say that
0 - 9 = very poor or not enough
10 - 15 = good
16 - 31 = very good

May this help you.
If you get your code even good for signal coverage, do you like to share it?

[linoko]

HI camolas,
I'm very like your project but i have some question.
Please send me if it is possible the schematic of device and post please the actual source code.
I try earlier version of the source code and i can't see device working.
I connect Siemens S35 the device send AT but cellphone did not answer with OK. Please help me with this project.

Best regards Konstantin
Sofia, Bulgaria

[aratti]

Mikebar, there is no need to waste pic memory space for checking the signal coverage.
The main reason is that the system will use "SMS" for answering and if signal is too poor than modem will not send the message till signal will return to an acceptable level.

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Linoko, very likely your siemens 35 use only "PDU mode" and you need "TEXT mode".

To check if your phone works in text mode, connect it to hyperteminal and Tx the following command:

AT+CMGF=1

press enter and check the answer.

If answer is "OK" then your phone works also in TEXT mode.

Al.

[mikebar]

Mikebar, there is no need to waste pic memory space for checking the signal coverage.
The main reason is that the system will use "SMS" for answering and if signal is too poor than modem will not send the message till signal will return to an acceptable level.

Al.

Thank you for the info.
But ALL the phones have the same behaviour you described or just some model? it is defined some standard for that behaviour or any producer think is "best solution"?

Thanks in advance.

[aratti]

Yes all phones behave in this way. Try to send a sms to your phone (switched off). You will receive it when your phone will be switched on again.

You can learn more at this link:http://communication.howstuffworks.com/sms.htm

Al.

[bethr]

Mikebar, there is no need to waste pic memory space for checking the signal coverage.
The main reason is that the system will use "SMS" for answering and if signal is too poor than modem will not send the message till signal will return to an acceptable level.

YEP, that's the reason why SMS messages are delayed for minutes hours (carrier dependant) BUT
U must have in mind that SIM card (were SMS are stored by default) has 20 memory location for only SMS if you try to send more, the answer becomes an "ERROR" instead and you wont know what exactly happen, if you really want to know what happen you should check GSM coverage !

Linoko, very likely your siemens 35 use only "PDU mode" and you need "TEXT mode".

To check if your phone works in text mode, connect it to hyperteminal and Tx the following command:

AT+CMGF=1

press enter and check the answer.

If answer is "OK" then your phone works also in TEXT mode.

Al.

please don't forget saving your phone settings using:
AT+CMGF=1 <CR><LF>
AT&W<CR><LF>