Giới thiệu vi điều khiển 8051

end

mov dptr,#0c000h movx @dptr,a

sjmp $ ;nhay tai cho

;RxD cua may phat va RxD cua may thu duoc noi voi nhau lam duong truyen data

;TxD cua may phat va TxD cua may thu duoc noi voi nhau lam xung clk

TRUYEÀN DÖÒ LIEÄU TÖØ MAÙY TÍNH ÑEÁN KIT VÑK 8051

B1. TRUYEÀN TÖØNG BYTE KÍ TÖÏ TÖØ MAÙY TÍNH ÑEÁN KIT VÑK

1. LÖU ÑOÀ

BEÂN TRUYEÀN (MAÙY TÍNH)

BEGIN

THIEÁT ÑAËT ÑÒA CHÆ VUØNG DÖÒ LIEÄU CUÛA CHÖÔNG TRÌNH, LÖU VAØ CAØI ÑAËT CAÙC NGAÉT CUÛA MAÙY TÍNH , ÑAËT PHUÔNG THÖÙC GIAO

TIEÁP CHUAÅN (2400 b/s, 8 bit, None Parity, 1 Stopbit)

KIEÅM TRA COÙ PHÍM NAØO ÑÖÔÏC AÁN ?

PHÍM F1

# PHÍM F1, F9

KIEÅM TRA COÙ PHÍM NAØO ÑÖÔÏC NHAÁN ?

PHÍM F9

HIEÅN THÒ MENU CUÛA CHÖÔNG TRÌNH

END

GOÏI CHÖÔNG TRÌNH HIEÅN THÒ VAØ TRUYEÀN KÍ TÖÏ ÑÖÔÏC NHAÁN

BEÂN NHAÄN (KIT VI ÑIEÀU KHIEÅN 8051):

BEGIN

KHÔÛI TAÏO 8051 ÔÛ CHEÁ ÑOÄ GIAO TIEÁP NOÁI TIEÁP NOÁI TIEÁP

KIEÅM TRA XEM ÑAÒ HEÁT ÑÒA CHÆ QUAÛN LYÙ VUØNG DL

YES

NAÏP ÑÒA CHÆ QUAÛN LYÙ VUØNG DÖÒ LIEÄU SEÒ ÑÖÔÏC GÖÛI TÔÙI

NHAÄN TÖØNG BYTE ÑÖÔÏC GÔÛI TÔÙI

END

2. CHÖÔNG TRÌNH

BEÂN TRUYEÀN (MAÙY TÍNH):

CHÖÔNG TRÌNH TRUYEÀN TÖØNG BYTE KÍ TÖÏ TÖØ MAÙY TÍNH

; STACK

stack segment stack

db 300 dup('?')

stack ends

;------------------------------------------ DATA ----------------------

Data Segment

;Messages

MENU_MS db '',0dh,0ah db '',0dh,0ah

db '* THE TRANSMITTED CHARACTERS * ‘,0dh,0ah

db '** --> Press To Redisplay This MENU ** ',0dh,0ah db '** --> Press To Exit This Program ** ’, 0dh,0ah

db 'Input characters from keyboard:'

db '$'

;

PROT_MS db '',0dh,0ah

ERR1_MS db 0dh,0ah,'*** Cannot Transmit ***',0dh,0ah

;

;PROGRAM PARAMETER STORAGE

CARD_BASE dw 03f8h ;Address of RS 232 card for all harware

;type except

INT_NUM db 0ch ;Offset in Bios table as follows SETUP_BYTE db 0bbh ;Default value

;

;Origin interrupt vector address to restore on exit O_INT_SEG dw 0000h ;segment

O_INT_OFF dw 0000h ;offset

;

;circular buffer and pointers:

CIRC_BUF db 20 dup(00h) ;Circular buffer dw 0

DATA_IN dw 0 ;imput pointer

DATA_OUT dw 0 ;output pointer

;

DATA Ends

;-------------------------------------- CODE -------------------------------------- CODE SEGMENT

ASSUME CS:CODE START:

;

;Establish addressability of program's data Segment mov ax,data

mov ds,ax

assume ds:data mov es,ax

assume es:data

;

;Display MENU at cursor

mov dx,offset menu_ms ;messages call show_message

;

;----------------------|

;Hardware Type |

;----------------------|

;

;Examine Ram location F000:FFFE to determine IBM hardware push ds ;Save program DS

mov dx,0f000h mov ds,dx

mov al,ds:[0fffeh] ;Code to AL

;

;Get addr of the RS232 card from BIOS data area

mov dx,0 ;Bios data area segment

mov ds,dx ;Data segment to Bios area

mov cx,ds:0400h ;Offset card 1

pop ds ;Restore program ds mov Card_Base,cx ;Save in program's data

;

;determine interrupt number:

; 0bh IRQ4 all other hardware

cmp al,0fdh ;Code for PCjr jne Set_Address

mov int_num,0bh

;

;----------------------------------|

;Save/Install Interrupt |

;----------------------------------|

;Obtain and save the segment/offset of the original communications

;interrup installed on entry using Dos service number 53

;of Int 21h Set_Address:

mov ah,53 ;Dos service request number mov al,Int_Num ;Interrup number (0bh or 0ch) int 21h

;

;ES:BX = segment/offset of original handler mov O_Int_Seg,es ;Save segment mov O_Int_Off,bx ;and offset

;

;Insert address of the interrup service routine in the Bios

;Label for interrup service routine is: RS232_INT

;use DOS service number 37 of INT 21h

mov ah,37 ;Dos service request number mov al,int_num ;Machine interrup number mov dx,offset cs:RS232_Int

push

ds	;Save program data segment
push	cs
pop	ds	;Set DS to segment base of
int	21h	;interrup service routine
pop	ds	;Restore program's ds