atmega32u4-16mu ATMEL Corporation, atmega32u4-16mu Datasheet - Page 5

• Manufacturer Part Number: atmega32u4-16mu
• Description: Atmega32u4 8-bit Avr Microcontroller With 32k Bytes Of Isp Flash And Usb Controller
• Manufacturer: ATMEL Corporation

2.2
2.2.1
2.2.2
2.2.3
2.2.4
7766A–AVR–03/08
Pin Descriptions
VCC
GND
Port B (PB7..PB0)
Port C (PC7,PC6)
stage with programmable gain, an on-chip calibrated temperature sensor, a programmable
Watchdog Timer with Internal Oscillator, an SPI serial port, IEEE std. 1149.1 compliant JTAG
test interface, also used for accessing the On-chip Debug system and programming and six soft-
ware selectable power saving modes. The Idle mode stops the CPU while allowing the SRAM,
Timer/Counters, SPI port, and interrupt system to continue functioning. The Power-down mode
saves the register contents but freezes the Oscillator, disabling all other chip functions until the
next interrupt or Hardware Reset. The ADC Noise Reduction mode stops the CPU and all I/O
modules except ADC, to minimize switching noise during ADC conversions. In Standby mode,
the Crystal/Resonator Oscillator is running while the rest of the device is sleeping. This allows
very fast start-up combined with low power consumption.
The device is manufactured using ATMEL’s high-density nonvolatile memory technology. The
On-chip ISP Flash allows the program memory to be reprogrammed in-system through an SPI
serial interface, by a conventional nonvolatile memory programmer, or by an On-chip Boot pro-
gram running on the AVR core. The boot program can use any interface to download the
application program in the application Flash memory. Software in the Boot Flash section will
continue to run while the Application Flash section is updated, providing true Read-While-Write
operation. By combining an 8-bit RISC CPU with In-System Self-Programmable Flash on a
monolithic chip, the ATMEL ATmega32U4 is a powerful microcontroller that provides a highly
flexible and cost effective solution to many embedded control applications.
The ATmega32U4 AVR is supported with a full suite of program and system development tools
including: C compilers, macro assemblers, program debugger/simulators, in-circuit emulators,
and evaluation kits.
Digital supply voltage.
Ground.
Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port B output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port B pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
Port B has better driving capabilities than the other ports.
Port B also serves the functions of various special features of the ATmega32U4 as listed on
page
Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port C output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port C pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
70.
ATmega32U4
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