How to use BC66 to send SMS

How to send text messages using BC66?

I’ve looked in all the datasheets and online, and I can’t seem to figure out which commands are used to send SMS’s.

Friendly Regards
Morten Hedegaard

Hi Morten,

the BC66 support SMS but most network operators won‘t. They must implement this feature in NB-IoT core network. Most operators (e.g. T-Mobile) provide SMS service only in LTE-Cat. M1 and higher but not in NB-IoT.
Check if your operator support it, before you try to implement this.

Best Regards,
Andreas Petter

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Thank you for your reply.
I can’t implement it because, the I cannot find the related AT commands anywhere.
Could you refer me to some documentation?

Friendly Greetings from
Morten

Hi Morten,

in BC66 doc you won’t find any hint about it. But in BC68 doc (AT commands reference manual), section 3, you will find 6 commands related to SMS service. It seams to be a standard command set according to 3GPP Commands (27.005).
I’ve never tested this service, because I know it for sure, it will not work here in Germany. :frowning:

Hi Morten
Process of sending SMS directly:

  1. Use AT+CMGF=1 to set the module to TEXT format.
  2. Query and set the center number through AT+CSCA (if the center number is correct, it is strongly recommended not to modify the center number).
  3. According to the requirement of sending short message character set format, the corresponding character set can be set through AT+CSCS=, such as AT+CSCS=“GSM”; AT+CSCS=“UCS2”, etc. (It is recommended to use GSM characters in English Set, other configuration according to SMS requirements)
  4. Perform AT+CGMS to send short messages. The target address can be the mobile phone number or the IMSI of (U)SIM, such as: AT+CGMS=“13795403834” (In order to avoid short message sending and receiving problems caused by roaming, it is recommended that all addresses Save as an international number format, starting with “+”)
  5. After executing AT+CGMS, enter the content to be sent.
  6. Press Ctrl+Z to send a short message; press ESC to exit the sending mode.

Send SMS from memory

  1. Use AT+CMDF=1 to set the module to TEXT format,
  2. Query and set the center number through AT+CSCA (if the center number is correct, it is strongly recommended not to modify the center number).
  3. According to the requirement of sending short message character set format, the corresponding character set can be set through AT+CSCS=, such as AT+CSCS=“GSM”; AT+CSCS=“UCS2”, etc.
  4. Execute AT+CGMW to send the content to the memory . The target address can be the mobile phone number or the IMSI of the card, such as: AT+CGMW=“13795403834”. After the command is executed successfully, it will return The index number .
  5. Then send a short message from the memory to the target address through AT+CMSS=.

Send SMS in “GSM” character set format from memory in TXT mode
For example
//The memory sends the English character “TEST” to 13795403834
AT+CMGF=1 //Set text message mode
OK
AT+CSCS=“GSM” //Set the TE input character set format to “GSM” format
OK
AT+CMGSW=“13795403834” //Enter the content of the short message, CTRL+Z to write, ESC to exit

TEST <Ctrl+Z>
+CMGW: 54 //Successfully write the short message, the index number in is 54

OK
AT+CMSS=54 //Send a short message to the target number “13795403834” set by AT+CMGW
+CMSS: 122

OK
AT+CMSS=54,“13795403834” //Send a short message to the new destination address “13795403834”
+CMSS: 123

OK

2. PDU mode

Sending short messages in PDU mode is similar to sending in text mode, and it needs to be configured to PDU mode through AT+CMGF=0. The sending mode is also divided into direct sending and sending through memory, corresponding to AT+CMGS and AT+CMGW.

Is there any way to get better error description, if all I get as a response to AT+CGMS is ERROR? AT+CMEE=2 does not help. AT+CMGF, AT+CSCA and AT+CSCS work fine.

Can you please write what is the current status of SMS and BC66. Is the SMS functionality stable in BC66? The pdf on the website states that SMS is under development.