AT91SAM7S256D-AU Atmel, AT91SAM7S256D-AU Datasheet - Page 132

• Manufacturer Part Number: AT91SAM7S256D-AU
• Description: ARM Microcontrollers - MCU 256K Flash SRAM 64K ARM based MCU
• Manufacturer: Atmel
• Series: SAM7S256r

Specifications of AT91SAM7S256D-AU

• Rohs: yes
• Core: ARM
• Processor Series: AT91SAM
• Data Bus Width: 16 bit/32 bit
• Maximum Clock Frequency: 55 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 64 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: LQFP-64
• Mounting Style: SMD/SMT
• Interface Type: 2-Wire, I2S, SPI, USART
• Length: 7 mm

20.2.5.3
20.2.5.4
Table 20-9.
The Flash command Write Page and Lock (WPL) is equivalent to the Flash Write Command. However, the lock
bit is automatically set at the end of the Flash write operation. As a lock region is composed of several pages, the
programmer writes to the first pages of the lock region using Flash write commands and writes to the last page of
the lock region using a Flash write and lock command.
The Flash command Erase Page and Write (EWP) is equivalent to the Flash Write Command. However, before
programming the load buffer, the page is erased.
The Flash command Erase Page and Write the Lock (EWPL) combines EWP and WPL commands.
This command is used to erase the Flash memory planes.
All lock regions must be unlocked before the Full Erase command by using the CLB command. Otherwise, the
erase command is aborted and no page is erased.
Table 20-10. Full Erase Command
Lock bits can be set using WPL or EWPL commands. They can also be set by using the Set Lock command
(SLB). With this command, several lock bits can be activated. A Bit Mask is provided as argument to the com-
mand. When bit 0 of the bit mask is set, then the first lock bit is activated.
In the same way, the Clear Lock command (CLB) is used to clear lock bits. All the lock bits are also cleared by the
EA command.
Table 20-11. Set and Clear Lock Bit Command
Step
...
n
n+1
n+2
n+3
n+4
n+5
...
Step
1
2
Step
1
2
Flash Full Erase Command
Flash Lock Commands
Handshake Sequence
...
Write handshaking
Write handshaking
Write handshaking
Write handshaking
Write handshaking
Write handshaking
...
Handshake Sequence
Write handshaking
Write handshaking
Handshake Sequence
Write handshaking
Write handshaking
Write Command (Continued)
MODE[3:0]
...
ADDR0
ADDR1
ADDR2
ADDR3
DATA
DATA
...
MODE[3:0]
CMDE
DATA
MODE[3:0]
CMDE
DATA
DATA[7:0]
...
Memory Address LSB
Memory Address
Memory Address
Memory Address
*Memory Address++
*Memory Address++
...
DATA[15:0] or DATA[7:0]
EA
0
DATA[15:0] or DATA[7:0]
SLB or CLB
Bit Mask
SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
132