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MESC TOOL NEWS:
MESCT-NC30WA_2-980801D
NC30WA V.3.00 Release 1
Precaution
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Please take note of the following problem in using C compiler NC30WA V.3.00 Release 1 (with assembler and integrated tool manager) for the M16C/60 series of microcomputers.
Problem
As the usage of #pragma EXT4MPTR was not mentioned in the user's manual, the function of #pragma EXT4MPTR is described below:
#pragma EXT4MPTR is a functional extension which shows a variable is a pointer accessing 4-Mbyte expanded ROM.
#pragma EXT4MPTR is effective as far as it is once declared prior to a function.
--------------------------------------------------------------------------
[Example]
struct tag{
int bitmap;
char code;
}*pointer;
#pragma EXT4MPTR pointer
main()
{
register int data;
data=pointer->bitmap;
}
--------------------------------------------------------------------------
In continuous (or repetitive) operations, setting a bank once as shown above produces codes that do not set banks subsequently and enables data to be efficiently referenced.
Note that when a number of banks are set with one function, option -fCBA (-fchange_bank_always) should be given to set banks every time data is referenced.
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