Calculadora 8051

;4 FUNCTION CALCULATOR PROGRAM

;Assumes 1.2MHz Clock for scan timing.

; TODO : Custom Character for the 'M' sign

; Check instances of multiple decimal point presses ( all covered ?)

;Reset vector

org 0000h

jmp start

;Start of the program

org 0100h

start: mov A,#030h ;1 line, 8 bits

call wrcmd

mov A,#LCD_SETVISIBLE + 4

call wrcmd

mov A,#LCD_SETDDADDR+15 ; Start at right hand side of the display

call wrcmd

mov A,#LCD_SETMODE + 3 ; Automatic Increment - Display shift left.

call wrcmd

mov 025h,#00h ; Set output mode (floating point).

call boundsbuffer ; Initialise the bounds buffer - used for error checking.

mov mode,#4 ; Initialise the constant buffer to 100. Primarily used for % ops.

mov digitcode,#031h

call storedigit

mov digitcode,#030h

call storedigit

mov digitcode,#030h

call storedigit

mov status,#00h ; variable used to determine the first key press after an operation.

mov bufferctr,#00h

mov opcounter,#00h

mov decimalcnt,#00h

call waitkey

halt: mov PCON,#1 ;Halt

;***********************************************************

;**** Floating Point Package ****

;********************************

$INCLUDE (FP52.ASM)

;Routine to peek arg at DPTR

argout: mov R0,#FP_NUMBER_SIZE

aoloop: movx A,@DPTR

anl A,#0F0h

rr a

rr a

rr a

rr a

add A,#aodata-$-3

movc A,@A+PC

call sndchr

movx A,@DPTR

anl A,#0Fh

add A,#aodata-$-3

movc A,@A+PC

call sndchr

inc DPTR

djnz R0, aoloop

ret

aodata: db '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'

;Routine to output character in A, preserving all but A.

sndchr: push R0B0

push R1B0

call getmode

mov digitcode,A

call storedigit

pop R1B0

pop R0B0

ret

;Routine to print error message at DPTR.

prterr: jmp wrstr

;Routine to handle input parameter error.

badprm: mov DPTR,#bpmsg

jmp wrstr

bpmsg: db 'Bad Parameter',0

;***********************************************************

;**** LCD Display Routines ****

;******************************

;LCD Registers addresses

LCD_CMD_WR equ 00h

LCD_DATA_WR equ 01h

LCD_BUSY_RD equ 02h

LCD_DATA_RD equ 03h

LCD_PAGE equ 80h

;LCD Commands

LCD_CLS equ 1

LCD_HOME equ 2

LCD_SETMODE equ 4

LCD_SETVISIBLE equ 8

LCD_SHIFT equ 16

LCD_SETFUNCTION equ 32

LCD_SETCGADDR equ 64

LCD_SETDDADDR equ 128

;Sub routine to write null terminated string at DPTR in program ram.

wrstr: mov P2,#LCD_PAGE

mov R0,#LCD_DATA_WR

wrstr1: clr A

movc A,@A+DPTR

jz wrstr2

movx @R0,A

call wtbusy

inc DPTR

jmp wrstr1

wrstr2: ret

;Sub routine to write null terminated string at DPTR in program ram.

wrstrslow: mov P2,#LCD_PAGE

mov R0,#LCD_DATA_WR

wrstr1s: clr A

movc