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Cx51 User's Guide

MDU_R515 Compiler Directive

Abbreviation None.
Arguments None.
Default Multiply/Division Unit support is disabled.
µVision Options — Target — Use On—Chip Arithmetic Unit.
Description 

The MDU_R515 directive enables support for the Multiple/Division Unit (MDU) of the Cast/Evatronix R80515. When this directive is specified the compiler uses the MDU to increase the speed of the following operations:

OperationImplementation
signed int mulIntrinsic
unsigned int mulIntrinsic
signed int div?C?SIDIVR515 routine
unsigned int div?C?UIDIVR515 routine
signed long mul?C?LMULR515 routine
unsigned long mul?C?LMULR515 routine
signed long div?C?SLDIVR515 routine
unsigned long div?C?ULDIVR515 routine
signed long shift left?C?LSHLR515 routine
unsigned long shift left?C?LSHLR515 routine
unsigned long shift right?C?ULSHRR515 routine
See Also NOMDU_R515
Example 
C51 SAMPLE.C MDU_R515

#pragma mdu_r515