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