Technical Support

C51: USING MDU_F120 AND MDU_R515 IN µVISION

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Information in this article applies to:

• C51 Version 7.20 and Later

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SYMPTOM

The MDU_F120 and MDU_R515 directives have been added to the C51 Compiler to support the MAC units of the Cygnal/Silicon Labs C8051F12x devices and Cast/Evatronix R80515 cores. The manual indicates that when these devices are selected from the Device Database that µVision will have a checkbox for Use On—Chip Arithmetic Unit in the Target window in the Project Options dialog. With µVision2 no such checkbox appears.

CAUSE

µVision support for these directives was added in µVision3. No new development is underway on µVision2.

RESOLUTION

You may download the latest updates from the Keil Website. The C51 V7.50 update includes a BETA release of µVision3.

If you continue using µVision2, you may enter these directives under Miscellaneous in the C51 window in the Project Options dialog.

MORE INFORMATION

• Refer to MDU_F120 in the Cx51 User's Guide.

SEE ALSO

• C51: USING THE 517 MULTIPLY/DIVIDE UNIT IN INTERRUPTS

Last Reviewed: Wednesday, September 28, 2005

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