實(shí)驗(yàn)器件：20片8X8LED點(diǎn)陣顯示屏，10片74LS164移位寄存器，10片74LS273數(shù)據(jù)鎖存器，2片74LS138譯碼器，1片PIC16F877A單片機(jī)。

       proteus元件庫(kù)中中沒(méi)有16X80點(diǎn)陣顯示屏，所以用20片8X8LED點(diǎn)陣屏拼裝而成。

       10片74LS164移位寄存器和10片74LS273數(shù)據(jù)鎖存器用于傳送和保存一行數(shù)據(jù)。

2片74LS138構(gòu)成4選16譯碼器用于行選。

實(shí)驗(yàn)截圖：

源程序:

 list  p=16f877A ; list directive to define processor
 #include <p16f877A.inc> ; processor specific variable definitions
 
 __CONFIG _CP_OFF & _WDT_OFF & _BODEN_OFF & _PWRTE_ON & _RC_OSC & _WRT_OFF & _LVP_ON & _CPD_OFF

; '__CONFIG' directive is used to embed configuration data within .asm file.
; The lables following the directive are located in the respective .inc file.
; See respective data sheet for additional information on configuration word.

;***** VARIABLE DEFINITIONS
w_temp  EQU 0x7D  ; variable used for context saving
status_temp EQU 0x7E  ; variable used for context saving
pclath_temp EQU 0x7F  ; variable used for context saving  

MAIN_LOOP:
 CALL LOAD_A_LINE    ;加載一行
 MOVF LINE_NUM,W    ;行選
 MOVWF PORTC     
 BSF  PORTB,RCK    ;將一行數(shù)據(jù)送入鎖存器
 NOP
 NOP
 BCF  PORTB,RCK
 CALL DELAY     ;延時(shí)
 INCF LINE_NUM    ;下一行
 BCF  LINE_NUM,4    ;一共16行，模16
 GOTO MAIN_LOOP

;加載一行
LOAD_A_LINE:      
 CLRF WORD_NUM    ;字號(hào)清零
LOAD_A_WORD:
 CLRF BYTE_NUM    ;字節(jié)號(hào)清零
LOAD_A_BYTE: 
 BCF  STATUS,C    ;清除C標(biāo)志位，為移位乘2做準(zhǔn)備
 RLF  LINE_NUM,W    ;每個(gè)字一行占兩個(gè)字節(jié)，所以乘2    
 ADDWF WORD_NUM,W    ;下面WORD_NUM每次加32，不用再乘
 ADDWF BYTE_NUM,W    ;行號(hào)X2 + 字號(hào)X32 + 字節(jié)號(hào)
 CALL ENCODE     ;查表，取出對(duì)應(yīng)的字節(jié)
 MOVWF PORTD     
 MOVLW D'8'
 MOVWF BYTE_BIT_COUNT   ;一個(gè)字節(jié)有8位
LOAD_A_BIT:
 BSF  PORTB,SCK    ;將PORTD最高位送入移位寄存器
 NOP
 NOP
 BCF  PORTB,SCK
 RLF  PORTD     ;移位，準(zhǔn)備將下一位送入移位寄存器
 DECFSZ BYTE_BIT_COUNT   ;循環(huán)8次
 GOTO LOAD_A_BIT

 INCF BYTE_NUM
 BTFSS BYTE_NUM,1    ;BYTE_NUM==2？一行有兩個(gè)字節(jié)
 GOTO LOAD_A_BYTE
 MOVLW D'32'
 ADDWF WORD_NUM    ;一個(gè)字32個(gè)字節(jié)，每次加32，使用時(shí)不用再乘32
 MOVF WORD_NUM,W
 SUBLW D'160'
 BTFSS STATUS,Z    ;WORD_NUM==160？5個(gè)字160個(gè)字節(jié)
 GOTO LOAD_A_WORD
 RETURN

;延時(shí)
DELAY:
 DECFSZ DELAY_REG
 GOTO DELAY
 RETURN
 
 
ENCODE:
 ADDWF PCL
 ;黑
 DT 0x3F,0xF8,0x21,0x08,0x29,0x28,0x25,0x48,0x25,0x88,0x3F,0xF8,0x01,0x00,0x01,0x00,
 DT 0x3F,0xF8,0x01,0x00,0xFF,0xFE,0x00,0x00,0x48,0x84,0x44,0x42,0x84,0x42,0x00,0x00
 ;龍
 DT 0x02,0x00,0x02,0x40,0x02,0x20,0x02,0x20,0x7F,0xFE,0x02,0x80,0x02,0x90,0x02,0x90,
 DT 0x04,0xA0,0x04,0xC0,0x08,0x80,0x09,0x80,0x12,0x82,0x20,0x82,0x40,0x7E,0x00,0x00
 ;江
 DT 0x20,0x00,0x10,0x00,0x13,0xFC,0x00,0x40,0x88,0x40,0x48,0x40,0x50,0x40,0x10,0x40,
 DT 0x10,0x40,0x20,0x40,0xE0,0x40,0x20,0x40,0x20,0x40,0x2F,0xFE,0x20,0x00,0x00,0x00
 ;大
 DT 0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0xFF,0xFE,0x01,0x00,0x02,0x80,
 DT 0x02,0x80,0x02,0x40,0x04,0x40,0x04,0x20,0x08,0x10,0x10,0x18,0x20,0x0E,0x40,0x04
 ;學(xué)
 DT 0x01,0x08,0x10,0x8C,0x0C,0xC8,0x08,0x90,0x7F,0xFE,0x40,0x04,0x8F,0xE8,0x00,0x40,
 DT 0x00,0x80,0x7F,0xFE,0x00,0x80,0x00,0x80,0x00,0x80,0x00,0x80,0x02,0x80,0x01,0x00

 END                       ; directive 'end of program'

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