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 con-
ventional CISC microcontrollers.
The ATmega169P provides the following features: 16K bytes of In-System Programmable Flash
with Read-While-Write capabilities, 512 bytes EEPROM, 1K byte SRAM, 53 general purpose I/O
lines, 32 general purpose working registers, a JTAG interface for Boundary-scan, On-chip
Debugging support and programming, a complete On-chip LCD controller with internal step-up
voltage, three flexible Timer/Counters with compare modes, internal and external interrupts, a
serial programmable USART, Universal Serial Interface with Start Condition Detector, an 8-
channel, 10-bit ADC, a programmable Watchdog Timer with internal Oscillator, an SPI serial
port, and five 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 and the LCD controller continues to run, allowing the user to maintain a timer base and
operate the LCD display while the rest of the device is sleeping. The ADC Noise Reduction
mode stops the CPU and all I/O modules except asynchronous timer, LCD controller and 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 com-
bined with low-power consumption.
The device is manufactured using Atmel’s high density non-volatile memory technology. The
On-chip ISP Flash allows the program memory to be reprogrammed In-System through an SPI
serial interface, by a conventional non-volatile 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 ATmega169P is a powerful microcontroller that provides a highly flex-
ible and cost effective solution to many embedded control applications.
The ATmega169P 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.
4
ATmega169P
8018IS–AVR–11/06
ATMEL [ ATMEL CORPORATION ]
