ADE7569ASTZF16 Analog Devices Inc, ADE7569ASTZF16 Datasheet - Page 113

• Manufacturer Part Number: ADE7569ASTZF16
• Description: IC ENERGY METER MCU 16K 64LQFP
• Manufacturer: Analog Devices Inc

Specifications of ADE7569ASTZF16

• Applications: Energy Measurement
• Core Processor: 8052
• Program Memory Type: FLASH (16 kB)
• Controller Series: ADE75xx
• Ram Size: 512 x 8
• Interface: I²C, SPI, UART
• Number Of I /o: 20
• Voltage - Supply: 3.135 V ~ 3.465 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Ic Function: Single Phase Energy Measurement IC
• Supply Voltage Range: 3.13V To 3.46V, 2.4V To 3.7V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: LQFP
• No. Of Pins: 64
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PROTECTING THE FLASH MEMORY
Two forms of protection are offered for this flash memory: read
protection and write/erase protection. The read protection ensures
that any pages that are read protected cannot be read by the end
user. The write protection ensures that the flash memory cannot
be erased or written over. This protects the end system from
tampering and can prevent the code from being overwritten in the
event of a runaway program.
Write/erase protection is individually selectable for all 32 pages.
Read protection is selected in groups of four pages (see Figure
94 for the groupings). The protection bits are stored in the last
flash memory locations, Address 0x3FFA through Address
0x3FFF (see Figure 96); four bytes are reserved for write/erase
protection, one byte is for read protection, and another byte to
set the flash protection key (PROTKY, Address 0xBB). The user
must enable write/erase protection for the last page, at a
minimum, for the entire protection scheme to work.
Note that the read protection does not prevent MOVC
commands from being executed within the code.
There is an additional layer of protection offered by a protection
security key (PROTKY). The user can set up a protection
security key so that the protection scheme cannot be changed
without this key. When the protection key has been configured,
it cannot be modified.
Enabling Flash Protection by Code
The protection bytes in the flash can be programmed using the
flash controller command and programming ECON to 0x08. In
this case, the EADRH, EADRL, PROTB1, and PROTB0 bytes
are used to store the data to be written to the 32 bits of write
protection. Note that the EADRH and EADRL registers are not
used as data pointers here but to store write protection data.
PROTKY
PROTB1
PROTB0
EADRH
PROTR
EADRL
0x3FFD
0x3FFC
0x3FFF
0x3FFE
0x3FFB
0x3FFA
0x3FF9
0x3E00
Figure 96. Flash Protection in Page 31
WDOG
31:28
LOCK
WP
WP
WP
WP
RP
31
23
15
7
27:24
WP
WP
WP
WP
RP
30
22
14
6
23:20
WP
WP
WP
WP
RP
29
21
13
5
PROTECTION KEY
19:16
WP
WP
WP
WP
RP
28
20
12
4
15:12
WP
WP
WP
WP
RP
27
19
11
3
11:8
WP
WP
WP
WP
RP
26
18
10
ADE7116/ADE7156/ADE7166/ADE7169/ADE7566/ADE7569
2
WP
WP
WP
WP
7:4
RP
25
17
9
1
WP
WP
WP
WP
3:0
RP
24
16
8
0
Rev. B | Page 113 of 152
The sequence for writing the flash protection follows:
1.
2.
3.
4.
5.
To enable read and write/erase protection for the last page only,
use the following 8052 code. Writing the flash protection
command to the ECON SFR initiates programming of the
protection bits in the flash.
; enable read protection on the last four
pages only
MOV PROTR,#07Fh
; set up a protection key of 0A3h. This
command can be
; omitted to use the default protection key
of 0xFF
MOV PROTKY,#0A3h
; write the flash key to the FLSHKY register
to enable flash
; access. The flash access key is not
configurable.
MOV FLSHKY,#3Bh
; write flash protection command to the ECON
register
MOV ECON,#08h
Set up the EADRH, EADRL, PROTB1, and PROTB0 SFRs
with the write/erase protection bits. When erased, the
protection bits default to 1, like any other bit of flash
memory. The default protection setting is for no protection.
To enable protection, write a 0 to the bits corresponding to
the pages that should be protected.
Set up the PROTR SFR with the read protection bits. Note
that every read protection bit protects four pages. To enable
the read protection bit, write a 0 to the bits that should be
read protected.
To enable the protection key, write to the PROTKY SFR.
If enabled, the protection key is required to modify the
protection scheme. The protection key, Flash Memory
Address 0x3FFA, defaults to 0xFF; if the PROTKY register
is not written to, it remains 0xFF. If the protection key is
written to, the PROTKY SFR must be written with this
value every time the protection functionality is accessed.
Note that after the protection key is configured, it cannot
be modified. Also note that the most significant bit of
Address 0x3FFA is used to enable a lock mechanism for
the watchdog settings (see the Watchdog Timer section for
more information).
Run the protection command by writing 0x08 to the
ECON SFR.
Reset the chip to activate the new protection.