用8051與1601LCD設計的計算器帶仿真和匯編源程序

ID:185854 · 發表于 2017-4-5 22:04

用8051與1601LCD設計的計算器仿真原理圖如下：

部分匯編源碼預覽：

/*******************************************************************************
************ LABCENTER ELECTRONICS ************
************ Proteus VSM Sample Design Code ************
************ Integer Calculator ( 2K Code Limit) ************
*******************************************************************************/
NAME KEYPAD
; This routine will read a character press from the keypad and return it in R7.
;Set up Segments for the Input Routine - No parameters.
?PR?input?KEYPAD SEGMENT CODE
PUBLIC input
?DT?input?KEYPAD SEGMENT DATA
RSEG ?DT?input?KEYPAD ; Local Variable Segment for Output Routine.
KEY_ROW1 equ 0EFh
KEY_ROW2 equ 0DFh
KEY_ROW3 equ 0BFh
KEY_ROW4 equ 07Fh
keyflags: ds 16
RSEG ?PR?input?KEYPAD ; Code Segment for Output Routine.
input:
keyscan:push DPH
push DPL
mov R0,#keyflags ; R0 addresses the key toggle bytes
mov R1,#KEY_ROW1 ; R1 address the keyboard row address
mov R2,#4 ; R2 counts rows
ksrow: mov P2,R1 ; Set row address to port P2
nop
mov A,P1 ; Read column data from port P1
mov R3,#4 ; R3 counts keys per row
anl A,#3Fh
ks0: rrc A ; Move next bit into carry
mov R4,A ; R4 preserves the row data
jc ks1 ; Jump if key not pressed
mov A,@R0 ; Test if key already pressed
mov @R0,#1 ; Flag pressed anyway
jz ksnew ; Jump if key newly pressed
jmp ks2
ks1: mov @R0,#0 ; Flag key as not pressed
ks2: inc R0 ; Loop for next key in this row
mov A,R4
djnz R3,ks0
mov A,R1 ; Jiggle R1 to address next row
rl A
mov R1,A
djnz R2,ksrow
clr A
mov R7,A ; Return zero - no (new) key press.
jmp ksend
ksnew: mov DPTR,#keycodes ; We've found a new key since last time:
mov A,R0 ; The key flag address (ordinal) is in R0
clr C
subb A,#keyflags
movc A,@A+DPTR
mov R7,A ; Move the Key into R7 to be returned.
ksend: mov P2,#0FFh
pop DPL
pop DPH
ret
;Data tables for returned row bits
keycodes:
db '7','8','9', '/'
db '4','5','6', '*'
db '1','2','3', '-'
db 'C','0','=', '+'
END