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GSM Modem receiving garbage data

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blizt

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I have two modems (ST-ERICSSON and Qualcomm). I'm testing my modems on hyper terminal to see if it is receiving the right sms or not. ST-Ericsson seems to be working fine but in qualcomm modem I'm receiving garbage data. I have set the baud rate from device settings also using at command but the problem persists. Any one has any idea what might be causing the problem or what am I doing wrong?

Note: For your reference following is the sms I'm getting in qualcomm mdem;
+CMGR: 0,,121
07912903983810F6040C91293323830397000071304021804002744456ECF682C95EB21A2B26D3CD
72BA198CE5AEB75931964C0683B16432198C2593C960AC980CC68AC960AC980CC68AC16030966C46
83B168351B8C45ABD96EAC580D77CBC972351B8D25A3D56C2C1AAB66BBB162B219AD6663E5703756
0DC6B2DD702C5ACD06
 
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You understand that the received data is in PDU mode?
 

Hi,

The characters are only 0..9 and A..F therefore I assume it is some Hex code.
Maybe a debugging Hex mode is enabled.

Klaus
 

I have changed the PDU mode to Text Mode. As I said, ST-ERICSSON is showing the exact sms I'm sending. I have tried using D-LINK modem and still getting the same response as qualcomm one :(
 

I don't understand your post. If the modem is selecting PDU format for message presentation, it doesn't "receive garbage". Or do you mean that the data coded by the PDU string is garbage?

PDU mode may be selected automatically because the message uses a different charset than the active charset.

The posted PDU string is apparently corrupted (contains spaces), thus I didn't try to decode it.
 

I don't understand your post. If the modem is selecting PDU format for message presentation, it doesn't "receive garbage". Or do you mean that the data coded by the PDU string is garbage?

PDU mode may be selected automatically because the message uses a different charset than the active charset.

The posted PDU string is apparently corrupted (contains spaces), thus I didn't try to decode it.

I'm getting the following sms on St-Ericsson modem which is what I'm sending:
+CMT: "num","","17/02/28,10:44:32+20"
D,17/02/28,10:40:30,num,1,2210,1110,2220,120,110,210,35,2300,7000,1500,456789,23400,45,34,230000,2100,507,560,150

And this is what I'm receiving on D-Link/Qualcomm Modem:
+CMGR: 0,,121
07912903983810F6040C912933238303970000713040218040 02744456ECF682C95EB21A2B26D3CD
72BA198CE5AEB75931964C0683B16432198C2593C960AC980C C68AC960AC980CC68AC16030966C46
83B168351B8C45ABD96EAC580D77CBC972351B8D25A3D56C2C 1AAB66BBB162B219AD6663E5703756
0DC6B2DD702C5ACD06

Even when I tried sending sms through modem it is giving error on command (at+cmgs). I'm really stuck here and I can not seem to understand what is causing this problem
 
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Even when I tried sending sms through modem it is giving error on command (at+cmgs). I'm really stuck here and I can not seem to understand what is causing this problem

You migh be aware that sending/receiving GSM data through modems is a process that comprises a set of commands in both sides which have to be called in the correct sequence. It seems that you are certainly missing/misusing some command/step, therefore instead of giving the resulted error, why don't you show the whole sequence of commands that you had used in both sides, sender and receiver ? In addition, it would be quite useful if you had provided the P/N or link for the datasheet of both modules ?
 

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