Conrad C-Control Pro Mega Series, Руководство пользователя, Страница: 93 / 240

84 Compiler
© 2008 Conrad Electronic
Compiler 5
5.1 General Features
This domain provides information on the Compiler’s properties and features which are independent of
the programming language used.
5.1.1 External RAM
The Application Board of Mega128 carries external RAM . This RAM is automatically recognized by
the Interpreter and used for the program to be carried out. For this reason a program memory of
appr. 63848 Bytes rather than appr. 2665 Bytes is available. For this it is not necessary to newly
compile the program.
If the SRAM is not needed it can be deactivated by JP7 and the ports will be free for other uses.
To deactivate the SRAM the jumper JP7 has to be moved to the left side (orientation: serial interface
shows to the left), such that the left pins of JP7 are connected.
5.1.2 Preprocessor
The Gnu Generic Preprocessor used here provides some additional functions which are
documented under http://nothingisreal.com/gpp/gpp.html . Only the functions described here however
have also together with the C-Control Pro Compiler been thoroughly tested. Using the here
undocumented functions will thus be at your own risk!
The C-Control development system contains a complete C-Preprozessor. The Preprocessor
processes the source text prior to Compiler start. The following commands are supported:
Definitions
By the command "#define" text constants are defined.
#define symbol text constant
Since the Preprocessor runs ahead of the Compiler at each appearance of symbol in the source text
the symbol will be replaced by text constant .
Example
#define PI 3.141
If a project consists of several sources then #define is a constant for all source files existing
following the file, in which the constant has been defined. It is thus possible to change the order of
source files in a project.