User`s guide

Configuration through the web interface
120
Supported Character Set
For SMS via GSM service, it is necessary to translate between the GSM 03.38 7-bit alphabet and
ASCII, which is the native character set for the Digi device and is the character set used in the CLI
and web UI.
The characters of ASCII and GSM 03.38 do not map one-to-one, and in fact some ASCII
characters must be represented in GSM 03.38 as multi-character escape sequences (per extensions
to the original GSM 03.38 alphabet). In the table below, such characters are shown as “0x1Bhh”
under the “GSM 03.38 Code” column. This notation indicates a two-character sequence, where
“hh” is a pair of hexadecimal digits.
In the reverse translation (from GSM 03.38 to ASCII), some of the GSM 03.38 characters have no
ASCII counterpart. These are replaced with ASCII space characters. One exception is the
INVERTED QUESTION MARK (0x60 in GSM 03.38) which is replaced with an ASCII
QUESTION MARK (0x3F) character.
The following table documents the supported characters and the mapping used between these two
alphabets. Note that “unknown” characters are replaced with space characters during the
translation. In the table below, such characters are shown as “0x20 *” under the “GSM 03.38
Code” column.
Notes for the table:
(1) The GRAVE ACCENT character (0x60) in ASCII has no counterpart in GSM 03.38. A
substitution is made using the APOSTROPHE (0x27) in its place.
* The characters marked with * indicate a substitution since the ASCII characters have
no counterpart in GSM 03.38. These characters are replaced with the SPACE (0x20)
character. As such, these characters are not supported in the Digi product support of
GSM short messages.