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AX51: ACCESSING EXTENDED CODE SPACE THE DS80C400


Information in this article applies to:

  • AX51 All Versions

QUESTION

Can I access the extended code space above 0x10000 on the Dallas 400 from inside an assembly module?

ANSWER

You can, if the device is in 16Mb contiguous mode. To set 16Mb mode, use the following instructions:

mov TA, #0AAh
mov TA, #055h
mov ACON, #02h

To locate a piece of code in the extended (ECODE) area, declare a segment, as follows:

myseg SEGMENT ECODE AT 0x10000
RSEG myseg
  (your code here)

...then simply ljmp to, or lcall, your code in extended code space.

ljmp 0x10000

SEE ALSO

AX51: LOCATING AN ECODE SEGMENT AT A FIXED ADDRESS

C51: EXAMPLE PROGRAMS FOR THE DALLAS 390 CONTIGUOUS MODE

Last Reviewed: Tuesday, June 01, 2004


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