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Applies to: C51 C Compiler


Information in this knowledgebase article applies to:


The Infineon XC800 series provides a 16-Bit-MDU (Multiply and Divide Unit). How can I get the C51 compiler to use it?


There is no direct MDU support in the C51 Compiler.
MDU registers are located in the system page. Since the compiler would have to assume a worst case scenario of paging condition this would imply some overhead of paging code. This lowers the advantage of using the MDU in generic code.

To make optimum use of the MDU it is recommended to use the built-in ROM functions for math.
You will see an increase in speed (ROM functions execute without waitstates) and a reduction of code-size (ROM functions are already present in BootROM).

To learn how to use XC800 ROM functions seeĀ C51: USING ROM LIBRARY IN INFINEON XC8XX DEVICES.


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Article last edited on: 2008-12-15 06:10:48

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