28.8.1. Control A
Name:
CTRLA
Offset:
0x00
Reset:
0x0000
Property:
PAC Write-Protection
Bit
15
14
13
12
11
10
9
8
CMDEX[7:0]
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
0
0
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
CMD[6:0]
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
0
0
0
0
0
0
0
Bits 15:8 – CMDEX[7:0]: Command Execution
When this bit group is written to the key value 0xA5, the command written to CMD will be executed. If a
value different from the key value is tried, the write will not be performed and the Programming Error bit in
the Status register (STATUS.PROGE) will be set. PROGE is also set if a previously written command is
not completed yet.
The key value must be written at the same time as CMD. If a command is issued through the APB bus on
the same cycle as an AHB bus access, the AHB bus access will be given priority. The command will then
be executed when the NVM block and the AHB bus are idle.
INTFLAG.READY must be '1' when the command is issued.
Bit 0 of the CMDEX bit group will read back as '1' until the command is issued.
Note:
The NVM Address bit field in the Address register (ADDR.ADDR) uses 16-bit addressing.
Bits 6:0 – CMD[6:0]: Command
These bits define the command to be executed when the CMDEX key is written.
CMD[6:0]
Group Configuration Description
0x00-0x01 -
Reserved
0x02
ER
Erase Row - Erases the row addressed by the ADDR register in the
NVM main array.
0x03
-
Reserved
0x04
WP
Write Page - Writes the contents of the page buffer to the page
addressed by the ADDR register.
0x05
EAR
0x06
WAP
0x07-0x0E -
Reserved
0x0F
WL
Write Lockbits- write the LOCK register
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
526