Sony Ericsson GR47/GR48 - Manual (Page 60)

9. EMBEDDED APPLICATIONS
60
LZT 123 7589 R1A
9. Embedded Applications
The radio device has the capability to store and run customer written code
in the form of a script during the processor’s idle time, through the use of
an on board interpreter.
9.1 Features
Main features of embedded applications are as follows.
• C based scripting language (Sony Ericsson specific);
• Over the air upgrade of scripts (NOT GSM software);
• Library of intrinsic functions;
• 2 scripts can be stored in the memory at any time but only 1 can be
active.
9.2 Implementation
The radio device has up to 44k of space available for storage of two scripts
in the scripting language and 25k of operating RAM. Structures included
in this language are:
• If - then - else statements
• While loops
• For loops
All hardware interfaces that are normally available to the radio device
through the AT commands are available to the embedded application.
Further drivers have been written such as M bus, keypad, SPI and I
2
C for
use by the embedded application (EA) through the use of the I/O pins.
9.2.1 Limitations
Since the radio device is processing the script using its own memory,
limitations are placed onto the scripts that are run.
• A direct comparison cannot be made to a fully compiled C program in
terms of size but a gauge of script size is that if each line were 128
characters long in the script then the script could be 350 lines long.
• Processing power is something that needs to be considered as the script
is run as a low priority process within the software. However, controller
mode stops GSM operation and provides all the processing power for
the script to be run. See the M2mpower Application Guide for more
details.
• Code cannot be ported directly from an existing application and loaded
directly onto the radio device. It must be re written in the Sony
Ericsson Mobile script language so that the radio device interpreter can
function correctly.