Z8F4822AR020SG Datasheet, PDF (194/323 Pages) Zilog, Inc. – High Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F64xx Series
Product Specification
174
4. Write the second unlock command 8CH to the Flash Control Register.
5. Rewrite the page written in Step 2 to the Page Select Register.
6. Write Flash memory using LDC or LDCI instructions to program the Flash.
7. Repeat Step 6 to program additional memory locations on the same page.
8. Write 00H to the Flash Control Register to lock the Flash Controller.
Page Erase
Flash memory can be erased one page (512 bytes) at a time. Page-erasing Flash memory
sets all bytes in a page to the value FFH. The Page Select Register identifies the page to be
erased. While the Flash Controller executes the Page Erase operation, the eZ8 CPU idles;
however, the system clock and on-chip peripherals continue to operate. The eZ8 CPU
resumes operation after the Page Erase operation completes. Interrupts that occur when
the Page Erase operation is in progress are serviced after the Page Erase operation is com-
plete. When the Page Erase operation is complete, the Flash Controller returns to its
locked state. Only pages located in unprotected sectors can be erased.
Observe the following procedure to perform a Page Erase operation:
1. Write 00H to the Flash Control Register to reset the Flash Controller.
2. Write the page to be erased to the Page Select Register.
3. Write the first unlock command 73H to the Flash Control Register.
4. Write the second unlock command 8CH to the Flash Control Register.
5. Rewrite the page written in Step 2 to the Page Select Register.
6. Write the Page Erase command 95H to the Flash Control Register.
Mass Erase
The Flash memory cannot be mass-erased by user code.
Flash Controller Bypass
The Flash Controller can be bypassed and the control signals for Flash memory can be
brought out to the GPIO pins. Bypassing the Flash Controller allows faster programming
algorithms by controlling the Flash programming signals directly.
Flash Controller Bypass is recommended for gang programming applications and large
volume customers who do not require in-circuit programming of Flash memory.
PS019924-0113
PRELIMINARY
Operation