ade7169f16 Analog Devices, Inc., ade7169f16 Datasheet - Page 102

• Manufacturer Part Number: ade7169f16
• Description: Single-phase Energy Measurement Ic With 8052 Mcu, Rtc And Lcd Driver
• Manufacturer: Analog Devices, Inc.

ADE7169F16
command. For example to write the protection value in
EADRH the two following commands need to be executed:
Notes on Flash Protection
The flash protection scheme is disabled by default so that none
of the pages of the flash are protected from reading or
writing/erasing.
The last page must be read and write/erase protected for the
protection scheme to work.
To activate the protection settings, the ADE7169F16 must be
reset after configuring the protection.
After configuring protection on the last page and resetting the
part, protections that have been enabled can only be removed
by mass erasing the flash memory. The protection bits are read
and erase protected by enabling read and write/erase protection
the last page, but the protection bits are never truly write
protected. Protection bits can be programmed modified from a
1 to a 0, even after the last page has been protected. In this way,
more protection can be added but none can be removed.
If a page of code is write/erase protected, it cannot be written
over even if an erase all command is issued. The write/erase
protected page will not be updated if new code is downloaded.
If a page is read protected, this part of the code cannot be read
or emulated.
The protection scheme is intended to protect the end system.
Protection should be disabled while developing and emulating
code.
Flash memory timing
Typical program and erase times for the flash memory are as
follows:
Command
WRITE BYTE
ERASE PAGE
ERASEALL
READ BYTE
ERASEPAGE and
WRITE BYTE
-
-
Following this protocol, the protection can be written to the
Flash using the same sequence as mentioned in the Enabling
Flash Protection by Code paragraph. When the part is reset the
protection will be effective.
Command ‘I ‘ with Data = Value of protection byte
0x3FFF
Command ‘F’ with Data = 0xC7
Bytes Affected
1 byte
512 bytes
16 kbytes
1 bytes
512 bytes
21ms
Flash Memory Timing
30us
20ms
200ms
100ns
Rev. PrD | Page 102 of 140
VERIFY BYTE
Note that the core microcontroller operation is idled until the
requested flash memory operation is complete. In practice, this
means that even though the Flash operation is typically initiated
with a two-machine-cycle MOV instruction (to write to the
Flash Control SFR (ECON, 0xB9)), the next instruction is not
executed until the Flash/EE operation is complete. This means
that the core cannot respond to interrupt requests until the
Flash/EE operation is complete, although the core peripheral
functions such as counter/ timers continue to count as
configured throughout this period.
IN CIRCUIT PROGRAMMING
Serial Downloading
The ADE7169F16 facilitates code download via the standard
UART serial port. The parts enter serial download mode after a
reset or a power cycle if the SDEN pin is pulled low through an
external 1 kΩ resistor. Once in serial download mode, the
hidden embedded download kernel executes. This allows the
user to download code to the full 16 kbytes of Flash memory
while the device is in circuit in its target application hardware.
Protection configured in the last page of the ADE7169F16
affects whether flash memory can be accessed in serial
download mode. Read protected pages cannot be read.
Write/erase protected pages cannot be written or erased. The
configuration bits cannot be programmed in serial download
mode.
Preliminary Technical Data
1 byte
100ns