ATMEGA16U4-MU Atmel, ATMEGA16U4-MU Datasheet - Page 349

• Manufacturer Part Number: ATMEGA16U4-MU
• Description: MCU AVR 16K FLASH 16MHZ 44-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA16U4-MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 26
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VQFN
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ATMEGA16U4-16MU; ATMEGA16U4-16MU

28.2.1
28.3
28.4
28.5
28.5.1
7766F–AVR–11/10
Signature Bytes
Calibration Byte
Parallel Programming Parameters, Pin Mapping, and Commands
Latching of Fuses
Signal Names
The fuse values are latched when the device enters programming mode and changes of the
fuse values will have no effect until the part leaves Programming mode. This does not apply to
the EESAVE Fuse which will take effect once it is programmed. The fuses are also latched on
Power-up in Normal mode.
All ATMEL microcontrollers have a three-byte signature code which identifies the device. This
code can be read in both serial and parallel mode, also when the device is locked. The three
bytes reside in a separate address space.
ATmega16U4 Signature Bytes:
ATmega32U4 Signature Bytes:
The ATmega16U4/ATmega32U4 has a byte calibration value for the internal RC Oscillator. This
byte resides in the high byte of address 0x000 in the signature address space. During reset, this
byte is automatically written into the OSCCAL Register to ensure correct frequency of the cali-
brated RC Oscillator.
This section describes how to parallel program and verify Flash Program memory, EEPROM
Data memory, Memory Lock bits, and Fuse bits in the ATmega16U4/ATmega32U4. Pulses are
assumed to be at least 250 ns unless otherwise noted.
In this section, some pins of the ATmega16U4/ATmega32U4 are referenced by signal names
describing their functionality during parallel programming, see
not described in the following table are referenced by pin names.
The XA1/XA0 pins determine the action executed when the XTAL1 pin is given a positive pulse.
The bit coding is shown in
When pulsing WR or OE, the command loaded determines the action executed. The different
commands are shown in
1. 0x000: 0x1E (indicates manufactured by ATMEL).
2. 0x001: 0x94 (indicates 16KB Flash memory).
3. 0x002: 0x88 (indicates ATmega16U4 device).
1. 0x000: 0x1E (indicates manufactured by ATMEL).
2. 0x001: 0x95 (indicates 32KB Flash memory).
3. 0x002: 0x87 (indicates ATmega32U4 device).
Table
Table
28-10.
28-9.
Figure 28-1
ATmega16/32U4
and
Table
28-6. Pins
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