A51: Bit-addressable Data Variables

Information in this article applies to:

• C51 Version 5.50a
• C51 Version 6.10a

QUESTION

How do I create a data variables that is bit-adderssable in the A51 assembler?

ANSWER

The following example program shows you how to accomplish this:

BIT_VAR         DATA    20h

FUNNY_ERROR     BIT     BIT_VAR.0
STAT_ERROR      BIT     BIT_VAR.1
ANOTHER_ERROR   BIT     BIT_VAR.2

cseg    at      0

        MOV     BIT_VAR, #0

        CLR     FUNNY_ERROR
        SETB    STAT_ERROR

        JNB     ANOTHER_ERROR, loop

loop:   jmp loop


END

SEE ALSO

• A51: Addressing Bits and Bytes
• A51: Error A17 (Invalid Byte Base in Bit Address Expression)

Last Reviewed: Thursday, February 25, 2021