character c cedilla ( SMALL) is displayed as CAPITAL

Question

I am facing an issue when displaying the C cedilla character (U+00E7 ç) used in French language, on a handset.

When it is sent via USSGW/SS7 as small c cedilla , it is displayed on handset as capital c cedilla (U+00C7 Ç).

For info, the character is encoded with gsm7bit.

Do you have any solution or idea for this situation?

Answer 1

The original ETSI TS 100 900 V7.2.0 (1999-07) Digital cellular telecommunications system (Phase 2+); Alphabets and language-specific information (GSM 03.38 version 7.2.0 Release 1998) defined byte 0x09 as Ç (capital C with cedilla).

Subsequently in GSM 03.38 to Unicode mappings, a clarification was made:

General notes: This table contains the data the Unicode Consortium has on how ETSI GSM 03.38 7-bit default alphabet characters map into Unicode. This mapping is based on ETSI TS 100 900 V7.2.0 (1999-07), with a correction of 0x09 to small c-cedilla, instead of capital C-cedilla.

and in the table:

0x08    0x00F2  #   LATIN SMALL LETTER O WITH GRAVE
0x09    0x00E7  #   LATIN SMALL LETTER C WITH CEDILLA
#0x09   0x00C7  #   LATIN CAPITAL LETTER C WITH CEDILLA (see note above)
0x0A    0x000A  #   LINE FEED

So there you have it, this character was remapped at some point. It is likely that you are correctly-encoding the character, but an older device or something using a library with the old standard is interpreting the character according to the original mapping, resulting in the capital letter.

I'm not seeing a mapping for Ç so it shouldn't appear any more.