atmega164-20pu ATMEL Corporation, atmega164-20pu Datasheet - Page 5

• Manufacturer Part Number: atmega164-20pu
• Description: 8-bit Microcontroller With 16/32/64k Bytes In-system Programmable Flash - Atmel Corporation
• Manufacturer: ATMEL Corporation

Comparison Between
ATmega164,
ATmega324 and
ATmega644
2593AS–AVR–06/05
The AVR core combines a rich instruction set with 32 general purpose working registers.
All the 32 registers are directly connected to the Arithmetic Logic Unit (ALU), allowing
two independent registers to be accessed in one single instruction executed in one clock
cycle. The resulting architecture is more code efficient while achieving throughputs up to
ten times faster than conventional CISC microcontrollers.
The ATmega164/324/644 provides the following features: 16/32/64K bytes of In-System
Programmable Flash with Read-While-Write capabilities, 512B/1K/2K bytes EEPROM,
1/2/4K bytes SRAM, 32 general purpose I/O lines, 32 general purpose working regis-
ters, Real Time Counter (RTC), three flexible Timer/Counters with compare modes and
PWM, 2 USARTs, a byte oriented 2-wire Serial Interface, a 8-channel, 10-bit ADC with
optional differential input stage with programmable gain, 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
software 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. In Power-save mode, the
asynchronous timer continues to run, allowing the user to maintain a timer base while
the rest of the device is sleeping. The ADC Noise Reduction mode stops the CPU and
all I/O modules except Asynchronous Timer and ADC, to minimize switching noise dur-
ing 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. In Extended Standby mode, both the main Oscillator and the Asyn-
chronous Timer continue to run.
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 program running on the AVR core. The boot program can use any
interface to download the application program in the application Flash memory. Soft-
ware 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-Program mable Flash on a monolithic ch ip, the Atmel
ATmega164/324/644 is a powerful microcontroller that provides a highly flexible and
cost effective solution to many embedded control applications.
The ATmega164/324/644 AVR is supported with a full suite of program and system
development tools including: C compilers, macro assemblers, program debugger/simu-
lators, in-circuit emulators, and evaluation kits.
Table 1. Differences between ATmega164 and ATmega644
Device
ATmega164
ATmega324
ATmega644
16 Kbyte
32 Kbyte
64 Kbyte
Flash
512 Bytes
EEPROM
1 Kbyte
2 Kbyte
1 Kbyte
2 Kbyte
4 Kbyte
RAM
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