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CodeVisionAVR
3.21 Hints
In order to decrease code size and improve the execution speed, you must apply the following rules:
• If possible use unsigned variables;
• Use the smallest data type possible, i.e. bit and unsigned char;
• The size of the bit variables, allocated to the program in the Project|Configure|C Compiler|Code
Generation|Bit Variables Size list box, should be as low as possible, in order to free registers for
allocation to other global variables;
• If possible use the TINY memory model;
• Always store constant strings in FLASH by using the flash keyword;
• After finishing debugging your program, compile it again with the Stack End Markers option
disabled.
3.22 Limitations
This version of the CodeVisionAVR C compiler has the following limitations:
• pointers to pointers are not supported yet;
• arrays of structures or unions can have only one dimension
• for the EVALUATION version the size of the compiled code is limited;
• the Philips PCF8563, Philips PCF8583, Dallas Semiconductor DS1302, DS1307, 4x40 character
LCD functions are not available in the EVALUATION version.
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