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GPRS disconnection problem

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alzomor

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HI

I am using SIM508
I can connect to server and send data.
when I shut down the module and power it again, I can't connect to server.
and I should wait for about 3 min with power off before connecting again in order to connect to server.

so , How could I overcome this problem?

Salam
Hossam Alzomor
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embeddedlover

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I too is using SIM508.
ur lucky that ur getting GPRS link within 3 minutes after power-on.
sometimes it takes hours for me to get the link.
I think there is no other option to speed up the module regarding GPRS link.
 

alzomor

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HI

I used the brown out interrupt in micro controller to detect power fail and close the socket.
Now I can reconnect immediately "in about 35 seconds"
but It may be Dependant on GSM operator rules

Salam
Hossam Alzomor
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embeddedlover

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Can you explain more about the brown out interrupt.
What difference it makes in using this interrupt during connection?
 

alzomor

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Hi

Sure
Some micro controllers can generate an interrupt when the VDD gose below some percentage.
in most cases this interrupt is used for saving state before power fail or switching to AUX power supply.
you should check datasheets for your microcontroller

Salam
Hossam Alzomor
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embeddedlover

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I have a small doubt here
If VDD reaches below certain level, ur state will be saved , this is regarding ur microcontroller state and not ur modem state.
If ur modem is off, then this state saving doesn't matter .Again u have to reset the modem and acquire GPRS link. This takes time.
Unless u reset the modem and check for link ur purpose will not be solved.
 

alzomor

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Hi

I get an interrupt when the VDD goes under some level.
within the ISR I Just close the socket.

That's all

Salam
Hossam alzomor
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