 |
 |
|
| W77E532_07 |
|
|||||||||||||||||
 WINBOND
|
| |||||||||||||||||
|
80 page 
W77E532/W77E532A Publication Release Date: November 19, 2007 - 80 - Revision A9 21. APPLICATION NOTE In-system Programming Software Examples This application note illustrates the in-system programmability of the Winbond W77E532A Flash EPROM microcontroller. In this example, microcontroller will boot from 64 KB APFLASH 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 ;******************************************************************************************************************* .chip 8052 .RAMCHK OFF .symbols CHPCON EQU 9FH TA EQU C7H SFRAL EQU ACH SFRAH EQU ADH SFRFD EQU AEH SFRCN EQU AFH ORG 0H LJMP 100H ; JUMP TO MAIN PROGRAM ;************************************************************************ ;* TIMER0 SERVICE VECTOR ORG = 000BH ;************************************************************************ ORG 00BH CLR TR0 ; TR0 = 0, STOP TIMER0 MOV TL0,R6 MOV TH0,R7 RETI ;************************************************************************ ;* 64K APFLASH MAIN PROGRAM ;************************************************************************ ORG 100H MAIN_64K: MOV A,P1 ; SCAN P1.0 ANL A,#01H CJNE A,#01H,PROGRAM_64K ; IF P1.0 = 0, ENTER IN-SYSTEM PROGRAMMING MODE JMP NORMAL_MODE |
