Z8F4822AR020SG Datasheet, PDF (195/323 Pages) Zilog, Inc. – High Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F64xx Series
Product Specification
175
For more information about bypassing the Flash Controller, refer to the Third Party Flash
Programming Support for Z8 Encore! MCUs Application Note (AN0117), which is avail-
able for download at www.zilog.com.
Flash Controller Behavior in Debug Mode
The following changes in Flash Controller behavior occur when the Flash Controller is
accessed using the On-Chip Debugger:
• The Flash Write Protect option bit is ignored
• The Flash Sector Protect Register is ignored for programming and erase operations
• 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 nec-
essary
• 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 operations. When writing multiple Flash pages, the Flash Controller must go
through the unlock sequence again to select another page.
Flash Control Register Definitions
This section defines the features of the following Flash Control registers.
Flash Control Register: see page 175
Flash Status Register: see page 177
Page Select Register: see page 177
Flash Sector Protect Register: see page 178
Flash Frequency High and Low Byte Registers: see page 179
Flash Control Register
The Flash Control Register, shown in Table 93, unlocks the Flash Controller for program-
ming and erase operations, or to select the Flash Sector Protect Register.
PS019924-0113
PRELIMINARY
Flash Control Register Definitions