51 Assembly Programming: 8×8 Dot Matrix Driver

;There is a question that requires you to change a C language program into an assembly language. The link is as follows:

;Looking at his original program, it drives the 8*8 LED dot matrix to display characters.

;

; According to the program, the dot matrix driving circuit is drawn. After running the C program, the display is as follows:

;

;

;All the characters displayed by the LED are given below. Some of the characters are very creative.

;The full code is as follows:

;8 * 8 LED dot matrix

    ORG   0000H

    JMP   START

;-----------------------

RED:

    DB  0x18,0x00,0x18,0x18,0x18,0x18,0x18,0x18;//i

    DB  0x0C,0x0C,0x0C,0x0C,0x0C,0x0C,0xFC,0xFC;//l

    DB  0x3C,0x42,0x42,0x42,0x42,0x42,0x42,0x3C;//o

    DB  0x00,0x00,0x44,0x44,0x44,0x44,0x28,0x10;//v

    DB  0x00,0x3E,0x02,0x02,0x3E,0x02,0x02,0x3E;//e

    DB  0x81,0xA5,0xDB,0xC3,0xA5,0x99,0x81,0xFF;//u

;-----------------------

START:

    MOV DPTR, #RED

    MOV R2, #254

LP0: MOV R3, #0

LP1: MOV R5, #100

LP2:MOV   R4, #0

LP3:MOV   A, R3

    ADD   A, R4

    CALL  DISP

    INC   R4

    CJNE  R4, #8, LP3

    DJNZ R5, LP2

;-----------------

    MOV A, R3

    ADD   A, #8

    MOV R3, A

    CJNE R3, #48, LP1

    SJMP LP0

;-----------------------

DISP:

    MOVC A, @A + DPTR

    MOV   P2, A

    MOV P0, R2

    MOV   A, R2

    RL    A

    MOV   R2, A

    DJNZ R7, $

    DJNZ R7, $

    MOV   P2, #0

    RIGHT

;-----------------------

END

; After submitting the assembler program, the following prompt appears:

;

;>_

;

;This kind of thing has happened many times, and there has been no result after appealing.

;

;Haha, the judgment ability and level of some network administrators on Baidu Zhidao are really hard to describe in words.

;

;

;The C program given in this question is as follows:

#include 

#define uchar  unsigned char

#define uint   unsigned int

uchar code  RED[] = {

    0x18,0x00,0x18,0x18,0x18,0x18,0x18,0x18,//i

    0x0C,0x0C,0x0C,0x0C,0x0C,0x0C,0xFC,0xFC,//l

    0x3C,0x42,0x42,0x42,0x42,0x42,0x42,0x3C,//o

    0x00,0x00,0x44,0x44,0x44,0x44,0x28,0x10,//v

    0x00,0x3E,0x02,0x02,0x3E,0x02,0x02,0x3E,//e

    0x81,0xA5,0xDB,0xC3,0xA5,0x99,0x81,0xFF //u

    };

void delay(uint t)

{

    for(; t > 0; t--);

}

void main()

{

    uchar r, j, q = 0, t = 0;

    while(1)  {

      for(r = 0; r < 40; r++) {

        for(j = q; j < q + 8; j++) {

          P0 = (~(0x01 << t));

          P2 = RED[j]; delay(200); P2 = 0;

          t++;  t %= 8;

        }

      }

      q += 8;  q %= 48;

    }

}

You can try to see if the functions of the two programs are the same.