Atmel ARM-based processors

Atmel ARM-based processors are microcontrollers and microprocessors integrated circuits, by Microchip Technology (previously Atmel), that are based on various 32-bit ARM processor cores, with in-house designed peripherals and tool support.

Overview

ARM licenses the core design for a series of 32-bit processors. ARM does not manufacture any complete silicon products, just intellectual property (IP). The ARM processors are RISC (reduced instruction set computing). This is similar to Microchip's AVR 8-bit products, a later adoption of RISC architecture. Whereas the AVR architecture used Harvard architecture exclusively, some ARM cores are Harvard (Cortex-M3) and others are Von Neumann architecture (ARM7TDMI).

Semiconductor companies such as Microchip take the ARM cores, which use a consistent set of instructions and register naming, and add peripheral circuits such as ADCs (analog to digital converters), clock management, and serial communications such as USART, SPI, I2C, CAN, LIN, USB, Ethernet, and LCD, Camera or Touch controllers. Microchip made efforts to adapt advanced peripherals and power management that used very little power and can operate independently without having the CPU core powered up (sleepwalking). They also provided for DMA between external interfaces and memories increasing data throughput with minimal processor intervention.

Microchip sells both MCUs (microcontroller units) that have internal Flash memory, and MPUs (microprocessor units) that use external memory.