Add option to set up SMS encoding

Author: Marcin Radomski

features/cellular/framework/API/CellularSMS.h

@@ -62,14 +62,20 @@ class CellularSMS {
         CellularSMSMmodeText
     };
 
+    enum CellularSMSEncoding {
+        CellularSMSEncoding7Bit,
+        CellularSMSEncoding8Bit,
+    };
+
     /** Does all the necessary initializations needed for receiving and sending SMS.
      *
      *  @param mode          enumeration for choosing the correct mode: text/pdu
      *  @return              NSAPI_ERROR_OK on success
      *                       NSAPI_ERROR_NO_MEMORY on memory failure
      *                       NSAPI_ERROR_DEVICE_ERROR on other failures
      */
-    virtual nsapi_error_t initialize(CellularSMSMmode mode) = 0;
+    virtual nsapi_error_t initialize(CellularSMSMmode mode,
+                                     CellularSMSEncoding encoding = CellularSMSEncoding::CellularSMSEncoding7Bit) = 0;
 
     /** Send the SMS with the given parameters
      *

features/cellular/framework/AT/AT_CellularSMS.cpp

@@ -245,8 +245,11 @@ nsapi_error_t AT_CellularSMS::set_csdh(int show_header)
     return _at.at_cmd_discard("+CSDH", "=", "%d", show_header);
 }
 
-nsapi_error_t AT_CellularSMS::initialize(CellularSMSMmode mode)
+nsapi_error_t AT_CellularSMS::initialize(CellularSMSMmode mode,
+                                         CellularSMSEncoding encoding)
 {
+    _use_8bit_encoding = (encoding == CellularSMSEncoding8Bit);
+
     _at.set_urc_handler("+CMTI:", callback(this, &AT_CellularSMS::cmti_urc));
     _at.set_urc_handler("+CMT:", callback(this, &AT_CellularSMS::cmt_urc));
 

features/cellular/framework/AT/AT_CellularSMS.h

@@ -39,7 +39,8 @@ class AT_CellularSMS: public CellularSMS, public AT_CellularBase {
 public:
     // from CellularSMS
 
-    virtual nsapi_error_t initialize(CellularSMSMmode mode);
+    virtual nsapi_error_t initialize(CellularSMSMmode mode,
+                                     CellularSMSEncoding encoding = CellularSMSEncoding7Bit);
 
     virtual nsapi_size_or_error_t send_sms(const char *phone_number, const char *message, int msg_len);