Industrial communications are at the heart of automated systems. Numerous defined standards exist, and these standards continue to grow as new industrial Ethernet protocols emerge. Atmel® microcontrollers provide the peripherals and the internal system architecture required to efficiently interface your product with leading field busses, industrial Ethernet standards, and growing wireless communications.

Industrial Communications Solutions

Field Bus

  • USART function with fractional baud rate on the Atmel AVR® XMEGA® family increases the flexibility on the choice of the system clock frequency and accuracy.
  • Dedicated RS485 mode for USART peripherals is available on most Atmel ARM® processor-based AT91SAM and AVR 32-bit microcontrollers
  • Rich number of DMA channels on Atmel megaAVR®, AVR XMEGA, AVR 32-bit and AT91SAM microcontrollers unloads the CPU during industrial communication transfers.
  • Multi-layer bus implementation on Atmel 32-bit microcontrollers enables true parallel data transfers and minimizes bus load limitation.
  • Optional external bus interface on several microcontrollers with up to 32-bit data supports dedicated ASSP for protocols such as Profibus.
  • Up to 12Mbps USART on the SAM3U and SAM9 microcontrollers provides support for external transceivers.
  • Single or dual CAN Controllers. V2.0A and V2.0B standard compliant, support independent message objects that are programmable on the fly, and ideal for field bus such as CANopen and DeviceNet. Program updates can be accomplished over the CAN bus if needed.

Atmel Products

TypeTopologyMicrocontrollerKey Advantage
FieldbusRS485 based (e.g. Profibus, Modbus)Microcontroller connected to the dedicated ASSP on the external busATmega1281





AVR UC3 B Series
Asynchronous external bus interface, DMA support
Microcontroller UART + transceiver ICSAM3UUp to 12MBs USART
CAN based (e.g. CANopen, DeviceNet)Microcontroller with intregated CAN peripheralATmega64M1


AVR UC3 C Series

ARM-based Solutions:
- SAM9263

Include up to 2 CAN peripheral with up to 15 mailboxes each

Product Families

Industrial Ethernet

The vertical integration of management execution systems with factory floor equipment has led to the convergence of the Ethernet TCP/IP protocol with industrial field busses. Several industrial Ethernet protocols have emerged, including Profinet, Ethernet/IP, ModbusTCP/IP, EtherCat, and Ethernet Powerlink. Each protocol addresses very specific needs, so requirements on the hardware platform vary accordingly.

Most industrial Ethernet automated systems do not require compliance with a PLC cycle times lower than a few milliseconds. For these applications, the industrial Ethernet protocol can be cost-effectively implemented in software on a microcontroller with an integrated standard Ethernet MAC peripheral. Due to their moderate flash size requirement, protocols like Modbus TCP can be implemented in a microcontroller. Atmel offers ARM-based and 32-bit AVR microcontrollers with up to 512KB of flash and an integrated Ethernet MAC unit. Benefits include:

  • 10/100 Ethernet Media Access Controller (EMAC) peripheral with chained buffer Direct Memory Access (DMA)
  • The EMAC DMA acts as a master on the internal multi layer bus with multiple internal SRAM blocks enabling a true parallel data transfer between the Ethernet frames and the application data.

Atmel SAM9 MPUs are also price-competitive solutions for implementing industrial Ethernet protocols, such as the Ethernet/IP standard, which requires a higher flash size and faster execution time. The Atmel SAM9 MPU, like the SAM9G45, offers a variety of benefits:

  • 400Mhz clocked ARM926EJ core with 32KB instruction and data caches speed execution time
  • Deterministic execution time with the use of the TCM (Tightly Coupled Memory) interface enables access to the internal SRAM with zero wait state at 400MHz. By dynamically configuring the SRAM as TCM, Ethernet frames can be analyzed at full speed without any copy to the cache.


Atmel Products

 TypeTopologyMicrocontrollerKey Advantage
Industrial EthernetProfinet RTSingle RJ45 port, microcontroller with integrated EMACSAM9G45EMAC with enhanced DMA, 400MHz ARM926 with TCM interface core
Ethernet/IPSAM9G20EMAC with enhanced DMA, 400MHz ARM926
ModbusTCP / PowerlinkARM-based Solutions:
- SAM9G20
EMAC with enhanced DMA, 512KB embedded flash
Profinet IRT and Ethercatmicrocontroller + external ASSP or FPGASAM9G45Dual EBI

For motion control applications, synchronism and short latency aspects are crucial. Protocols such as Profinet IRT or Ethercat address these requirements and are suited for systems with a sub-millisecond PLC times. In this case, specific ASSP or FPGA solutions must be used. The Atmel SAM9G45, with its dual EBI feature, lets designers integrate the industrial Ethernet communication module with mimimal performance impact. Data transfers between the ASIC or FPGA can be handled by the DMA unit, in parallel with external RAM access.

Product Families

Wireless Communication

Wireless communication in the industrial automation is increasingly popular, providing an easier way to install and connect mobile or inaccessible equipment.

Industrial control equipment such as PLC and DCS IO modules primarily utilize IEEE802.11 WLAN and Bluetooth standards. Atmel 32-bit microcontrollers and microprocessors feature an embedded multimedia card interface that supports connection to an SDIO WLAN or Bluetooth module.

Industrial sensors or actuators have demanding requirements for power consumption, board space, and implementation cost. For these products, IEEE802.15.4 technology, such as Zigbee or Wireless-HART is most appropriate. Atmel offers complete Wireless Solutions based on our low-power microcontrollers and RF transceivers. Benefits include:

  • Excellent RF performance enables longer range and more robust RF link
  • Best in class power consumption
  • Lowest system cost

Atmel Products

 TypeTopologyMicrocontrollerKey Advantage
WLANMicrocontroller +
WIFI module over SDIO
AVR UC3 A Series

ARM-based Solutions:
- SAM9G20
SDcard peripheral
Bluetooth basedMicrocontroller +
Bluetooth module over SDIO
SAM9G20SDcard peripheral
based (proprietary, W-HART)
Single-chipATmega128RFA1AVR with RF
Microcontroller +
RF transceiver
SAM3 Transceivers
Low power consumption RF Up to 512KB Flash/64KB SRAM

Reference Designs

[ + ] Wireless Thermostat with SAM4LC Reference Design

[ + ] Wireless SoC with RFMDs RF6505/6575/6555

[ + ] ISM Band PCB Antenna Reference Design

[ + ] UART to Ethernet Gateway with SAM4S

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