W79E648 Datasheet, PDF (62/80 Pages) Winbond – Fast 8051 Compatible microcontroller with a redesigned Processor

Preliminary W79E648
14. IN-SYSTEM PROGRAMMING
14.1 The Loader Program Locates at LDFlash Memory
CPU is Free Run at APFlash memory. CHPCON register had been set #03H value before CPU has
entered idle state. CPU will switch to LDFlash memory and execute a reset action. H/W reboot mode
will switch to LDFlash memory, too. Set SFRCN register where it locates at user's loader program to
update APFlash bank 0 or bank 1 memory. Set a SWRESET ( CHPCON=#83H) to switch back
APFlash after CPU has updated APFlash program. CPU will restart to run program from reset state.
14.2 The Loader Program Locates at APFlash Memory
CPU is Free Run at APFlash memory. CHPCON register had been set #01H value before CPU has
entered idle state. Set SFRCN register to update LDFlash or another bank of APFlash program. CPU
will continue to run user's APFlash program after CPU has updated program. Please refer
demonstrative code to understand other detail description.
15. H/W WRITER MODE
This mode is for the writer to write / read Flash EPROM operation. A general user may not enter this
mode.
The Timing For Entering Flash EPROM
Mode on the Programmer
EA
PSEN
ALE
P2.7
P2.6
P3.7
P3.6
RST
300ms
10ms
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
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