The high four bits of the microcontroller P1 port are used as buttons, and the low four bits are used as output display program-EEWORLD

Collect

;There is a corresponding C51 program
;This program mainly reflects the design of the button based on the single-chip microcomputer,
;Use the lower eight-bit LED display of P1 port, just to show the experimental results
;2007-06-05
             org           0000h
             ljmp start
             org           0060h
start:
             mov         a,#0f0h           ;Prepare to set the upper four bits of P1 port to high for inputmov
             p1         ,a              ;Set the upper four bits of P1 port to highmov
             a         ,p1              ;Read P1 portswap
             a         ;                Exchange the upper four bits and lower four bits of A, and put the upper four bits of P1 port data to the lower four
             bitsanl          a,#0fh         ;Shield the upper four bits, remove the upper four bits that do not need to be displayed, or do not remove them, which will not affect the displaymov
             p1          ,a             ;Send the read number to P1 port for display (displayed through the LED connected to the lower four bits of P1 port)
             ljmp start ;             Rescanend

Keywords：MCU Reference address：The high four bits of the microcontroller P1 port are used as buttons, and the low four bits are used as output display program

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