ATmega64(L)
RESET
Reset input. A low level on this pin for longer than the minimum pulse length will gener-
ate a reset, even if the clock is not running. The minimum pulse length is given in Table
19 on page 53. Shorter pulses are not guaranteed to generate a reset.
Input to the inverting Oscillator amplifier and input to the internal clock operating circuit.
Output from the inverting Oscillator amplifier.
AVCC is the supply voltage pin for Port F and the A/D Converter. It should be externally
connected to V
CC
, even if the ADC is not used. If the ADC is used, it should be con-
nected to V
CC
through a low-pass filter.
AREF is the analog reference pin for the A/D Converter.
This is a programming enable pin for the SPI Serial Programming mode. By holding this
pin low during a Power-on Reset, the device will enter the SPI Serial Programming
mode. PEN has no function during normal operation.
A comprehensive set of development tools, application notes and datasheetsare avail-
able for download on http://www.atmel.com/avr.
XTAL1
XTAL2
AVCC
AREF
PEN
Resources
7
2490LS–AVR–10/06
ATMEL [ ATMEL CORPORATION ]
