w79e532 Winbond Electronics Corp America, w79e532 Datasheet - Page 71

• Manufacturer Part Number: w79e532
• Description: 8-bit Microcontroller
• Manufacturer: Winbond Electronics Corp America

21. APPLICATION NOTE
In-system Programming Software Examples
This application note illustrates the in-system programmability of the Winbond W79E(L)532 Flash
EPROM microcontroller. In this example, microcontroller will boot from 64 KB ÔãÙÿôû bank and
waiting for a key to enter in-system programming mode for re-programming the contents of 64 KB
APFlash. While entering in-system programming mode, microcontroller executes the loader program
in 4KB LDFlash bank. The loader program erases the 64 KB APFlash then reads the new code data
from external SRAM buffer (or through other interfaces) to update the 64KB APFlash.
If the customer uses the reboot mode to update his program, please enable this b3 or b4 of security
bits from the writer. Please refer security bits for detail descrption
EXAMPLE 1:
;*******************************************************************************************************************
;* Example of 64K APFlash program: Program will scan the P1.0. if P1.0 = 0, enters in-system
;* programming mode for updating the content of APFlash code else executes the current ROM code.
;* XTAL = 24 MHz
;*******************************************************************************************************************
CHPCON
TA
SFRAL
SFRAH
SFRFD
SFRCN
MAIN_64K:
;************************************************************************
;* TIMER0 SERVICE VECTOR ORG = 000BH
;************************************************************************
;************************************************************************
;* 64K APFlash MAIN PROGRAM
;************************************************************************
.chip 8052
.RAMCHK OFF
.symbols
ORG
LJMP
ORG 00BH
CLR TR0
MOV TL0,R6
MOV TH0,R7
RETI
ORG
MOV A,P1
ANL A,#01H
CJNE A,#01H,PROGRAM_64K
JMP NORMAL_MODE
EQU
EQU
EQU
EQU
EQU
EQU
0H
100H
100H
9FH
C7H
ACH
ADH
AEH
AFH
; JUMP TO MAIN PROGRAM
; TR0 = 0, STOP TIMER0
; SCAN P1.0
; IF P1.0 = 0, ENTER IN-SYSTEM PROGRAMMING MODE
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Publication Release Date: November 21, 2005
W79E532/W79L532
Revision A5