Atmel AT91SAM

Atmel ARM-based processors are microcontrollers and microprocessors integrated circuits, by Atmel, that are based on various 32-bit ARM processor cores, with Atmel-designed peripherals and tool support. Atmel ARM families complement their 8-bit AVR and 32-bit AVR32 lines of microcontrollers.

The "SAM" moniker in Atmel part numbers stands for "SMART Atmel microcontroller". The SMART brand includes application-specific ARM-based parts for Wi-Fi, such as the SmartConnect and Smart Direct lines, as well as ARM-based ICs meant for smart energy products such as gas and power meters. The SMART line is a key component of Atmel’s Internet of Things (IoT) strategy.

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 Atmel’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 Atmel 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, CAN, LIN, and I2C. Atmel 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.

Atmel sells both MCUs (microcontroller units) that have internal Flash memory, and MPUs (microprocessor units) that use external memory. In addition to the chips themselves, Atmel offers demo boards, both on its website, and through distribution channels such as Digi-key, Element14, Arrow, Avnet, Future Electronics, and Mouser.

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