Keil Logo

BIT Assembler Statement

Arguments
symbol BIT address
Description

The BIT statement assigns an address (in the range 20h-2Fh or an 8051 bit-addressable SFR) to the specified symbol. The symbol may not be redefined.

In addition, the BIT statement may create a bit name for the following bit-addressable items:

  • Absolute addresses from 20H.0-2FH.7. For example, 23H.2.
  • SFR bits which are in the bit-addressable space. For example, P3.3, or PSW.7. This creates an absolute bit because SFR symbols are absolute.
  • Bits based on bytes contained in bit-addressable data sections. This results in relocatable bits if the bit-addressable data section is relocatable.
See Also

BSEG, CODE, DATA, IDATA, XDATA

Example
DATA_SEG        SEGMENT DATA BITADDRESSABLE

RSEG            DATA_SEG              ; Relocatable
                                      ; bit-addressable
                                      ; segment

BITS:           DS      1             ; A 1-byte
                                      ; bit-addressable
                                      ; variable

ALARM           BIT     BITS.0        ; Bit 0 in BITS
D1_OPEN         BIT     ALARM+1       ; Bit 1 in BITS
D2_OPEN         BIT     ALARM+2       ; Bit 2 in BITS

P1_2            BIT     90h.2         ; SFR P1.2
  Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.

Change Settings

Privacy Policy Update

Arm’s Privacy Policy has been updated. By continuing to use our site, you consent to Arm’s Privacy Policy. Please review our Privacy Policy to learn more about our collection, use and transfers
of your data.