flashee.asm

aduc812精典源代码下载,适合初学者

;********************************************************************
;
; Author        : ADI - Apps            www.analog.com/MicroConverter
;
; Date          : 28 May 1999
;
; File          : FlashEE.asm
;
; Hardware      : ADuC812
;
; Description   : Demonstrates use of the on-chip read/write 640 byte
;                 FlashEE data memory space.  Stores a sequence of
;                 button presses (INT0 button on eval board) in data
;                 FlashEE space.  Replays sequence on LED when board
;                 is reset or power cycled.  Will store the sequence
;                 until another is recorded with a new set of button
;                 presses.  To record a new sequence, just wait until
;                 the current one finishes playing (LED is off) and
;                 enter new sequence via button (INT0).
;
; NOTE:         : DO NOT write to FlashEE addresses above page 159!
; -----           The 640 bytes are stored in pages 0 thru 159 (9Fh)
;                 as four bytes per page.  Writing to pages above
;                 those documented can permanently lock you out of
;                 the chip.  See ADuC812 data sheet and errata sheet
;                 for details (www.analog.com/microconverter).
;
;********************************************************************

$MOD812                         ; Use 8052&ADuC812 predefined symbols

LED      EQU    P3.4            ; P3.4 drives red LED on eval board
BUTTON   EQU    P3.2            ; button on eval board drives P3.2
PREVIOUS EQU    F0              ; flag to hold previous button value
READ     EQU    01h             ; FlashEE command:  'read page'
WRITE    EQU    02h             ; FlashEE command:  'write page'
VERIFY   EQU    04h             ; FlashEE command:  'verify page'
ERASE    EQU    05h             ; FlashEE command:  'erase page'
ERASEALL EQU    06h             ; FlashEE command:  'erase all'

;____________________________________________________________________
                                                  ; BEGINNING OF CODE
CSEG

ORG 0000h

        SETB    LED             ; turn LED off
        MOV     A,#15
        CALL    DELAY           ; pause 1.5 seconds

        MOV     EADRL,#0        ; set data FlashEE address to page 0

; READ FLASH/EE DATA and indicate values via LED on and off times...

READPG: MOV     ECON,#READ      ; read current 4byte page of FlashEE
                                ; into EDATA1,2,3,4
        MOV     A,#1
        CJNE    A,EDATA4,EMPTY  ; if EDATA4 is 1, then page contains
                                ; valid data from previous write
                                ; otherwise, jump to EMPTY

        CALL    BLINK           ; flash LED for period determined
                                ; by FlashEE data just read

        INC     EADRL           ; increment to next FlashEE page addr
        MOV     A,EADRL
        CJNE    A,#0A0h,CMPRR   ; if address is less than 160..
CMPRR:  JC      READPG          ; ..then jump to read the next page
                                ; (DO NOT write to pages above 159!)

; WHEN "PLAY" SEQUENCE IS FINIISHED, wait for button press...

EMPTY:  SETB     LED
        JB      BUTTON,$        ; wait for first button press
        MOV     A,#1
        CALL    DELAY           ; pause 100ms
        JB      BUTTON,EMPTY    ; ensure button wasn't false trigger

; IF BUTTON PRESSED, then ERASE and go into "RECORD" mode...

        MOV     ECON,#ERASEALL  ; clear all data FlashEE memory
        MOV     EADRL,#0

; CAPTURE AND RECORD in FLASH/EE space time between button edges...

GETNEW: CALL    GETVAL

        MOV     EDATA1,DPL      ; place DPTR in EDATA1,2,3
        MOV     EDATA2,DPH
        MOV     EDATA3,DPP
        MOV     EDATA4,#1       ; put 1 in EDATA4 as identifier
        MOV     ECON,#ERASE
        MOV     ECON,#WRITE     ; write EDATA1-4 into current page of
                                ; FlashEE data memory

        MOV     ECON,#VERIFY    ; verify current page is same as..
        MOV     A,ECON          ; ..EDATA1-4.  if same, ECON <- 0
        JNZ     EMPTY           ; if verify fails, jump to EMPTY

        INC     EADRL           ; increment to next FlashEE page addr
        MOV     A,EADRL
        CJNE    A,#0A0h,CMPRG   ; if EADRL<A0h..
CMPRG:  JC      GETNEW          ; ..then jump to get the next value
                                ; (DO NOT write to pages above 159!)

; WHEN FLASH/EE DATA SPACE IS FULL...

        SETB     LED     ; code will end up here only after 160 button
                        ; edges.  no more can be recorded, so code
        JMP     $       ; just waits for a reset or power cycle.

;____________________________________________________________________
                                                        ; SUBROUTINES

BLINK:                          ; turn LED on or off for the duration
                                ; based on the value in EDATA3/2/1
        CPL     LED

        MOV     DPL,#0
        MOV     DPH,#0          ; clear DPTR
        MOV     DPP,#0

AGAIN1: INC     DPTR            ; increment DPTR..                  2
        MOV     A,DPP           ;                                   1
        CJNE    A,EDATA3,CMPR3  ;                                   2
        MOV     A,DPH           ;                                   1
        CJNE    A,EDATA2,CMPR2  ;                                   2
        MOV     A,DPL           ;                                   1
        CJNE    A,EDATA1,CMPR1  ;                                   2
CMPR3:  NOP                     ;                                   1
        NOP                     ;                                   1
        NOP                     ;                                   1
CMPR2:  NOP                     ;                                   1
        NOP                     ;                                   1
        NOP                     ;                                   1
CMPR1:  JC      AGAIN1          ; ..until DPTR>=EDATA3/2/1          2

        RET

; this routine directly controls LED on and off times based on data
; previously stored by a similar routine (GETVAL) which measures
; BUTTON on and off times.

;____________________________________________________________________

GETVAL:                         ; get a value based on duration of
                                ; button press
        MOV     DPL,#0
        MOV     DPH,#0          ; clear DPTR
        MOV     DPP,#0

        CPL     LED

AGAIN2: INC     DPTR            ; keep incrementing DPTR..          2
        NOP                     ;                                   1
        NOP                     ;                                   1
        NOP                     ;                                   1
        NOP                     ;                                   1
        NOP                     ;                                   1
        NOP                     ;                                   1
        NOP                     ;                                   1
        JNB     LED,CHKB        ;                                   2
        JNB     BUTTON,AGAIN2   ;                                   2
        RET                     ; ..until the button changes state
CHKB:   JB      BUTTON,AGAIN2   ;                                   2
        RET

; DPTR (DPP,DPH,DPL) now holds a number that represents the length of
; time between button edges.  this data will be stored in FlashEE
; space for use in controlling LED on and off times in "play" mode.

;____________________________________________________________________

DELAY:                          ; delay 100ms * A

DLY0:   MOV     R7,#200         ; 200 * 500us = 100ms
DLY1:   MOV     R6,#229         ; 229 * 2.17us = 500us
        DJNZ    R6,$            ; sit here for 500us
        DJNZ    R7,DLY1         ; repeat 200 times (100ms total)
        DJNZ    ACC,DELAY       ; repeat 100ms delay ACC times
        RET

;____________________________________________________________________

END