Z8F0113HJ005EG Datasheet, PDF (156/245 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F0823 Series
Product Specification
141
• Programming operations are not limited to the page selected in the Page Select
register
• Bits in the Flash Sector Protect register can be written to one or zero
• The second write of the Page Select register to unlock the Flash Controller is not
necessary
• The Page Select register can be written when the Flash Controller is unlocked
• The Mass Erase command is enabled through the Flash Control Register
Caution: For security reasons, the Flash Controller allows only a single page to be opened for
write/erase. When writing multiple Flash pages, the Flash controller must repeat the un-
lock sequence to select another page.
Flash Control Register Definitions
This section defines the features of the following Flash Control registers.
Flash Control Register: see page 141
Flash Status Register: see page 143
Flash Page Select Register: see page 143
Flash Sector Protect Register: see page 145
Flash Frequency High and Low Byte Registers: see page 145
Flash Control Register
The Flash Controller must be unlocked using the Flash Control (FTCTL) Register before
programming or erasing the Flash memory. Writing the sequence 73H 8CH, sequentially,
to the Flash Control Register unlocks the Flash Controller. When the Flash Controller is
unlocked, the 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.
PS024315-1011
PRELIMINARY
Flash Control Register Definitions