Z8F0830HH020SG Datasheet, PDF (137/257 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore!^® F0830 Series
Product Specification
119
Flash Control Register
The Flash Controller must be unlocked using the Flash Control Register before program-
ming or erasing Flash memory. Writing the sequence 73H 8CH, sequentially, to the Flash
Control Register unlocks the Flash Controller. When the Flash Controller is unlocked,
Flash memory can be enabled for mass erase or page erase by writing the appropriate
enable command to the FCTL. Page erase applies only to the active page selected in Flash
Page Select Register. Mass erase is enabled only through the On-Chip Debugger. Writing
an invalid value or an invalid sequence returns the Flash Controller to its Locked state.
The write-only Flash Control Register shares its register file address with the read-only
Flash Status Register.
Table 72. Flash Control Register (FCTL)
Bit
7
6
5
4
3
2
1
0
Field
FCMD
RESET
0
0
0
0
0
0
0
0
R/W
W
W
W
W
W
W
W
W
Address
FF8H
Bit
[7:0]
FCMD
Description
Flash Command
73H = First unlock command.
8CH = Second unlock command.
95H = Page erase command (must be third command in sequence to initiate page erase).
63H = Mass erase command (must be third command in sequence to initiate mass erase).
5EH = Enable Flash Sector Protect Register access.
PS025113-1212
Flash Control Register Definitions