Sunday, February 28, 2016

8051 Absolute Addressing Mode

Absolute Addressing Mode

  • In this mode, the operand is an absolute address
  • Instructions associated with this mode are ACALL and AJMP
  • These are 2-byte instructions where the 11-bit absolute address is specified as the operand
  • Upper 5-bits of PC are not modified
  • Lower 11-bits are loaded from this instruction
  • Branch address must be within current 2k bytes page of program memory
  • 64K bytes program memory is divided in to thirty-two 2K bytes pages
  • Example:
  • ACALL PORT_INIT
    PORT_INIT: MOV P0, #0FH
    PORT_INIT is a subroutine which should be located within 2K bytes



Related topics:
8051 Addressing Modes   |   8051 Register Addressing Mode   |   8051 Direct Addressing Mode   |   8051 Indirect Addressing Mode   |   8051 Immediate Addressing Mode   |   8051 Relative Addressing Mode   |   8051 Long Addressing Mode   |   8051 Indexed Addressing Mode   |   8051 External Addressing Mode

List of topics: 8051

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