AT90USB647-MU Atmel, AT90USB647-MU Datasheet - Page 353

• Manufacturer Part Number: AT90USB647-MU
• Description: MCU, 8BIT, 64K FLASH, USB, 64QFN
• Manufacturer: Atmel

Specifications of AT90USB647-MU

• Controller Family/series: AT90
• No. Of I/o's: 48
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Cpu Speed: 16MHz
• No. Of: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 64KB
• Oscillator Type: External, Internal
• Package: 64QFN EP
• Device Core: AVR
• Family Name: AT90
• Maximum Speed: 20 MHz
• Ram Size: 4 KB
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Program Memory Type: Flash
• Number Of Programmable I/os: 48
• Interface Type: SPI/TWI/USART/USB
• On-chip Adc: 8-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 4
• Lead Free Status / Rohs Status: Details

28.5
28.5.1
28.5.2
7593K–AVR–11/09
Entering the Boot Loader Program
Regular application conditions.
Boot Reset Fuse
Table 28-2.
Note:
Table 28-3.
Note:
The bootloader can be executed with three different conditions:
A jump or call from the application program. This may be initiated by a trigger such as a com-
mand received via USART, SPI or USB.
The Boot Reset Fuse (BOOTRST) can be programmed so that the Reset Vector is pointing to
the Boot Flash start address after a reset. In this case, the Boot Loader is started after a reset.
After the application code is loaded, the program can start executing the application code. Note
that the fuses cannot be changed by the MCU itself. This means that once the Boot Reset Fuse
BLB0 Mode
BLB1 Mode
1
2
3
4
1
2
3
4
1. “1” means unprogrammed, “0” means programmed
1. “1” means unprogrammed, “0” means programmed
Boot Lock Bit0 Protection Modes (Application Section)
Boot Lock Bit1 Protection Modes (Boot Loader Section)
BLB02
BLB12
1
1
0
0
1
1
0
0
BLB01
BLB11
1
0
0
1
1
0
0
1
Protection
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.
Protection
No restrictions for SPM or (E)LPM accessing the Boot
Loader section.
SPM is not allowed to write to the Boot Loader section.
SPM is not allowed to write to the Boot Loader section,
and (E)LPM executing from the Application section is not
allowed to read from the Boot Loader section. If Interrupt
Vectors are placed in the Application section, interrupts
are disabled while executing from the Boot Loader section.
(E)LPM executing from the Application section is not
allowed to read from the Boot Loader section. If Interrupt
Vectors are placed in the Application section, interrupts
are disabled while executing from the Boot Loader section.
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