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SFR Memory

The 8051 provides 128 bytes of memory for Special Function Registers (SFRs). SFRs are bit, byte, or word-sized registers that are used to control timers, counters, serial I/O, port I/O, and peripherals. Refer to Special Function Registers for more information.


  • SFR memory may be accessed directly using the MOV instruction. It may not be accessed indirectly.

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