z8f083a ZiLOG Semiconductor, z8f083a Datasheet - Page 126

• Manufacturer Part Number: z8f083a
• Description: High-performance 8-bit Microcontrollers
• Manufacturer: ZiLOG Semiconductor

Table 70. Flash Control Register (FCTL)
Flash Control Register Definitions
.
BITS
FIELD
RESET
R/W
ADDR
PS026308-1207
Flash Control Register
Flash Status Register
W
7
0
routines are factory programmed and cannot be altered by you. The NVDS operation is
described in detail. See
The NVDS routines are triggered by a user code: CALL into Zilog memory. Code
executing from Zilog memory must be able to read and write other locations within Zilog
memory. User code must not be able to read or write Zilog memory.
The Flash controller must be unlocked using the Flash control register before
programming or erasing the Flash memory. Writing the sequence
to the Flash control register unlocks the Flash controller. When the Flash controller is
unlocked, the Flash memory is 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.
FCMD—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
The Flash status register indicates the current state of the Flash controller. This register is
read at any time. The read-only Flash status register shares its Register File address with
the write-only Flash control register.
W
6
0
W
5
0
Non Volatile Data Storage
W
4
0
FCMD
FF8H
W
3
0
on page 129.
Z8 Encore!
W
2
0
Product Specification
73H 8CH
W
1
0
®
F083A Series
, sequentially,
Flash Memory
W
0
0
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