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A166: USING DPP1 AND DPP2 IN ASSEMBLER ROUTINES


Information in this article applies to:

  • C166 Version 3.12
  • C166 Version 4.01

QUESTION

On page 121 of the C166 Compiler manual (06.96) it states that "The usage of DPP1 and DPP2 is not allowed in assembler subroutines". I would like to use either DPP1 or DPP2 in my assembler to speed up an operation. Is that possible?

ANSWER

Yes, you may use DPP1 and DPP2 in assembler routines providing:

  1. You disable interrupts while using them.
  2. You restore the original values of the registers when you return to C or re-enable interrupts.

Last Reviewed: Saturday, July 09, 2005


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