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Questions about GPRS Modem --mc35

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MyOwn

New Member
I want to use mc35 for transmiting data with gprs network, and encount some questions,
I should get my own IP address with PPP, when executing command:
AT+CGDATA=PPP,1 ENTER
I received string of "connect", and then about ten times of unknown characters, At last, "No Carrier" returned, and seemed return to deactivated state, What shall I do? thanks ahead.
 

Eclipsed

New Member
By GPRS you mean General Packet Radio Service, right? You have to have a GSM account(and sim card) through a cell service provider and that carrier usually has to enable GPRS on that account.What do you mean PPP and what does an IP address have to do with GPRS?
 

MyOwn

New Member
Eclipsed said:
By GPRS you mean General Packet Radio Service, right? You have to have a GSM account(and sim card) through a cell service provider and that carrier usually has to enable GPRS on that account.What do you mean PPP and what does an IP address have to do with GPRS?
:?:
1 You are completely right with the meanings of GPRS!
2 My system is composed of MC35, a SIM card, which communicates with MC35 through 232 interface, and a MCU. Now I can send ATD*** command to dial a telephone, and attach to GPRS network with command AT+CGATT=1.
3 Of my understanding, IP is used for transmiting data throuth GPRS net, which is based on TCP/IP mechanism.
4 Presently, My difficulty is how I can get my own IP address? When I tried to convert MC35 to data mode with AT+CGDATA=PPP,1, MC35 returnd:
CONNECT
followed with a series of unknown characters, and at last with NO CARRIER
Where is wrong?

5In addition, What's the meanings of GSM account?
 

MyOwn

New Member
Eclipsed said:
GSM is the type of cell network that GPRS operates on.Sorry if I am insulting your intelligence with these questions but, Do you have a valid account with a GSM carrier that allows GPRS? Is GPRS enabled through that carrier? What part of the world are you in?

http://www.gsmworld.com/technology/gprs/index.shtml
:?:
Fact is I misunderstood you.
1 I ever bought a product intergating with MC35, which could attach to GPRS net and transmit data with other MT. That is to say, I think it is of my mistake, not the enviroment.
2 When I use Dial Network integrated in PC, with telephone number of *99***1#, and attachment of AT+CGDCONT=1,"IP","CMNET", the terminal can activate a PDP context. Then with a program using socket, I can get the local IP. I even supervised the data sent from 232 port, it includes AT ENTER, AT+CGDCONT=1,"IP","CMNET" ENTER, and then some data different from AT command, which I think may be PPP content. How do you think of it?
Here CMNET is the APN.
3 I am in China. I know little about GPRS, and with little data of MC35. I want to know how I can know whether I have a valid account(my SIM card is valid now)?
4 Thanks for your bearing with my low IQ :)
 

Eclipsed

New Member
You would have to have a valid account with China Mobile(I believe is your cell carrier).Meaning you would have to pay them for using the GPRS service.
 
Hi friend!
Sorry for my bad English, I am Brazilian.
The subject is, I use 1 module Siemens MC35i, and don't get to establish one connection in my provider in situation the Telecom Italia Mobile Brazil (TIM BRASIL).
Before me send any string I received 9 strings with multiple characters ascII, Sample:
~ÿ}#À!}!}#} }9}"}&} }*} } }'}"}(}"}%}&(?â}?}#}%Â#}%-c~

Are these sequences PPP?
When receive this string I return other string?
I using the Module MC35i in Hiper Terminal in serial port. These don't send commands alone. I will owe send some command?

Thanks.

Eduardo Rhowmert
 

ArieSmit

New Member
Same problem here

Hi Eduardo,

we have the same problem, it's weird and i've been struggeling for hours now.
I'm checking the dutch market now for an answere.

regards


arie
 
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