W78E516B Datasheet, PDF (25/26 Pages) Winbond – 8-BIT MICROCONTROLLER

W78E516B
INC SFRAL
MOV A,SFRAL
JNZ BLANK_CHECK_LOOP
INC SFRAH
MOV A,SFRAH
CJNE A,#0H,BLANK_CHECK_LOOP
JMP PROGRAM_64KROM
; NEXT ADDRESS
; END ADDRESS = FFFFH
BLANK_CHECK_ERROR:
MOV P1,#F0H
MOV P3,#F0H
JMP $
;*******************************************************************************
;* RE-PROGRAMMING 64KB APROM BANK
;*******************************************************************************
PROGRAM_64KROM:
MOV DPTR,#0H
MOV R2,#00H
MOV R1,#00H
MOV DPTR,#0H
MOV SFRAH,R1
MOV SFRCN,#21H
MOV R6,#5AH
MOV R7,#FFH
MOV TL0,R6
MOV TH0,R7
; THE ADDRESS OF NEW ROM CODE
; TARGET LOW BYTE ADDRESS
; TARGET HIGH BYTE ADDRESS
; EXTERNAL SRAM BUFFER ADDRESS
; SFRAH, TARGET HIGH ADDRESS
; SFRCN(C7H) = 21 (PROGRAM 64K)
; SET TIMER FOR PROGRAMMING, ABOUT 50 µS.
PROG_D_64K:
MOV SFRAL,R2
; SFRAL(C4H) = LOW BYTE ADDRESS
MOVX A,@DPTR ; READ DATA FROM EXTERNAL SRAM BUFFER
MOV SFRFD,A
; SFRFD(C6H) = DATA IN
MOV TCON,#10H ; TCON = 10H, TR0 = 1,GO
MOV PCON,#01H ; ENTER IDLE MODE (PRORGAMMING)
INC DPTR
INC R2
CJNE R2,#0H,PROG_D_64K
INC R1
MOV SFRAH,R1
CJNE R1,#0H,PROG_D_64K
;*****************************************************************************
; * VERIFY 64KB APROM BANK
;*****************************************************************************
MOV R4,#03H
; ERROR COUNTER
MOV R6,#FBH
; SET TIMER FOR READ VERIFY, ABOUT 1.5 µS.
MOV R7,#FFH
MOV TL0,R6
MOV TH0,R7
MOV DPTR,#0H ; The start address of sample code
MOV R2,#0H
; Target low byte address
MOV R1,#0H
; Target high byte address
MOV SFRAH,R1 ; SFRAH, Target high address
MOV SFRCN,#00H ; SFRCN = 00 (Read ROM CODE)
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Publication Release Date: February 2000
Revision A3