# Sierra Wireless: SMS with AT, special characters

**URL:** <https://forum.sierrawireless.com/t/sierra-wireless-sms-with-at-special-characters/8456>\
**Category:** MC/EM Series\
**Created:** [February 26, 2016, 7:53am UTC](https://forum.sierrawireless.com/t/sierra-wireless-sms-with-at-special-characters/8456 "2016-02-26T07:53:02Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![chades](https://avatars.discourse-cdn.com/v4/letter/c/7993a0/32.png) [@chades](https://forum.sierrawireless.com/u/chades)\
**Post date:** [February 26, 2016, 7:53am UTC](https://forum.sierrawireless.com/t/sierra-wireless-sms-with-at-special-characters/8456/1 "2016-02-26T07:53:02Z")

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Hi!

We are using Sierra Wireless cards in our systems for SMS sending.  
We access them as serial modems with the AT/Hayes commands.

## If we try to send a testmessage with a character of the MSM extended-charset (e.g. {, [, }, }, |, …) we get an error. Messages without any of these characters are fine.

at  
OK  
AT+CMGF=1  
OK  
AT+CMGS=“12345678”

> test ok

+CMGS: 164  
OK

AT+CMGS=“12345678”

> test [nok]

## +CMS ERROR: 305

Is there a way to send that characters? Maybe we need a special encoding or something??  
Thanks for help!

Chris

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**Author:** ![krima919](https://avatars.discourse-cdn.com/v4/letter/k/94ad74/32.png) [@krima919](https://forum.sierrawireless.com/u/krima919)\
**Post date:** [February 26, 2016, 8:39am UTC](https://forum.sierrawireless.com/t/sierra-wireless-sms-with-at-special-characters/8456/2 "2016-02-26T08:39:24Z")

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I think you should be able to do this in PDU mode.  
AT+CMGF=0

If you are not familiar with PDU encoding there are several PDU generators available on the web.