What is the Plotter?
The Plotter is an Industrial Ethernet demo by PHYTEC that brings together EtherCAT stacks by Kunbus, PLC programming by CODESYS, the latest AM64x/AM243x silicon from TI, and AWS IoT Greengrass services enabling fleet management to showcase real-time motor control synchronized across a daisy chain of independent systems.
The purpose of this over-engineered CNC machine demo is to showcase TI’s new AM64x/AM243x silicon, their pre-integrated industrial Ethernet protocols from Kunbus, and PHYTEC’s familiarity with integrating these into novel designs.
About the demo
A phyCORE-AM64x development kit presides over the entire system as the EtherCAT Main device. The AM64x’s Cortex-A53s runs Arago Linux built with Yocto and leverages CODESYS runtime services to establish a EtherCAT network on one of its standard Ethernet ports. The EtherCAT network is used to communicate to a series of daisy-chained Secondary devices, based on the PLC-style phyGATE-AM243x.
Each Secondary device is responsible for a single axis of the Pen Plotter and receive commands and synchronization information via G-code instructions sent over EtherCAT from the Main device. The Secondary devices all run freeRTOS from TI’s MCU+ SDK on their Cortex-R5s and include pre-integrated industrial Ethernet stacks (EtherCAT, Profinet, EtherNET/IP and others) that run on the AM243x’s Industrial Communication Subsystems (PRU-ICSSG).
Industrial Communication
Each line of G-code is packed into a standard Ethernet frame where X, Y, and Z axis information is organized into its own datagram. Each EtherCAT Secondary device then receives the full Ethernet frame and filters out the datagram it needs (according to the plotter axis it is responsible for) while at the same time adding state information back in on-the-fly, before passing the full frame to the next device in the daisy chain. A single Ethernet frame is therefore shuttled down and back along the daisy chain of devices with a well-defined cycle time, enabling each device to synchronize their processes.
AWS Cloud Integration
The phyCORE-AM64x EtherCAT Main device is provisioned with AWS IoT Greengrass via the meta-aws project, which enables support to be built directly into the Linux software image using Yocto. AWS IoT Greengrass components deployed on the EtherCAT Main device allow cloud-based tools such as AWS IoT Sitewise to analyze and monitor data being broadcasted from the edge.
Interested in a development kit?
PHYTEC phyBOARD-AM64x and phyCORE-AM64x 
Scan the QR code below (or use your phone camera) to see the development kit and contact PHYTEC Sales!
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Note on EtherCAT
EtherCAT is a real-time industrial Ethernet protocol that enables short cycle times and low jitter on a super flexible connection topology; it enables deterministic control of modular machines in noisy environments such as a manufacturing floor.
PHYTEC will use the terms “Main” and “Secondary” to describe EtherCAT device roles. Note that the official EtherCAT standard still uses outdated “Master” and “Slave” terminology.
Ready to get started?
Let’s go! Learn more about PHYTEC SOMs