ATmega32U4 Atmel Corporation, ATmega32U4 Datasheet - Page 346

• Manufacturer Part Number: ATmega32U4
• Manufacturer: Atmel Corporation

Specifications of ATmega32U4

• Flash (kbytes): 32 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 14
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 26
• Ext Interrupts: 13
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 12
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 3.3
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 4
• Output Compare Channels: 12
• Input Capture Channels: 2
• Pwm Channels: 8
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

28. Memory Programming
28.1
7766F–AVR–11/10
Program And Data Memory Lock Bits
The ATmega16U4/ATmega32U4 provides six Lock bits which can be left unprogrammed (“1”) or
can be programmed (“0”) to obtain the additional features listed in
only be erased to “1” with the Chip Erase command.
Table 28-1.
Note:
Table 28-2.
BLB12
BLB11
BLB02
BLB01
LB2
LB1
BLB0 Mode
LB Mode
Lock Bit Byte
1
2
3
1
2
3
4
Memory Lock Bits
1. “1”: unprogrammed, “0”: programmed
Lock Bit Byte
Lock Bit Protection Modes
BLB02
LB2
1
1
0
1
1
0
0
Bit No
BLB01
LB1
7
6
5
4
3
2
1
0
1
0
0
1
0
0
1
(1)
Description
–
–
Boot Lock bit
Boot Lock bit
Boot Lock bit
Boot Lock bit
Lock bit
Lock bit
Protection Type
No memory lock features enabled.
Further programming of the Flash and EEPROM is disabled in
Parallel and Serial Programming mode. The Fuse bits are locked in
both Serial and Parallel Programming mode.
Further programming and verification of the Flash and EEPROM is
disabled in Parallel and Serial Programming mode. The Boot Lock
bits and Fuse bits are locked in both Serial and Parallel
Programming mode.
No restrictions for SPM or (E)LPM accessing the Application
section.
SPM is not allowed to write to the Application section.
SPM is not allowed to write to the Application section, and (E)LPM
executing from the Boot Loader section is not allowed to read from
the Application section. If Interrupt Vectors are placed in the Boot
Loader section, interrupts are disabled while executing from the
Application section.
(E)LPM executing from the Boot Loader section is not allowed to
read from the Application section. If Interrupt Vectors are placed in
the Boot Loader section, interrupts are disabled while executing
from the Application section.
(1)(2)
ATmega16U4/32U4
0
0
0
(1)
ATmega16/32U4
Default Value
Table
ATmega16U4RC/32U4RC
1
1
1
1
1
1
1
1
28-2. The Lock bits can
(1)
346