Raspberry Pi CM3+ based SBC ships with CODESYS

Raspberry Pi CM3+ based SBC ships with CODESYS

Oct 25, 2021 — by Eric Brown

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Kontron’s “Pi-Tron CM3+” controller SBC is based on the Raspberry Pi CM3+ and offers 2x LAN, 2x USB, 2x COM, 2x DIO, CAN, micro-HDMI, MIPI DSI/CSI, 40-pin GPIO, and CODESYS support.

Since Kontron acquired PiXtend’s line of Raspberry Pi based controllers a year ago, we have been waiting for some new Pi-based products from the German embedded computing firm. Kontron has now delivered with the Baseboard BL Pi-Tron CM3+, a sandwich-style SBC built around the Raspberry Pi Compute Module 3+ (CM3+).

Like Kontron’s Raspberry Pi SBC based PiXtend controller boards (see farther below), the Pi-Tron CM3+ supports the CODESYS automation software for programming industrial controller applications that comply with the IEC 61131-3 industrial standard.

Baseboard BL Pi-Tron CM3+
(click images to enlarge)

“Thanks to its open interfaces and comprehensive security features, CODESYS has distinguished itself as an optimal Industry 4.0 platform and facilitates data exchange between any IIoT networks,” says Kontron. Other RPi Compute Module based controllers with CODESYS support include TechBase’s ModBerry products.

The wording of the Kontron announcement implies that the Pi-Tron CM3+ is already available. We see no sign of a previous announcement but we found this April 2021 article written by a Kontron exec about Kontron’s Raspberry Pi based product line, which mentions the Pi-Tron and PiXtend products.

The Raspberry Pi CM3+, which followed the similarly 1.2GHz, quad-core Cortex -A53 based CM3 module used on Kontron’s earlier Passepartout (or Raspberry Pi Industrial Starterkit), adds 8GB to 32GB eMMC options and offers a wider -20 to 70° operating range than the CM3. The CM3+ appears to be easier to acquire in volume compared to the quad -A72 RPi CM4, which may be one reason why Kontron is using it here. The Kontron article linked to above says Kontron is working on developing CM4-based products.

We have seen the CM3+ on a variety of industrial controllers, panel PCs, and other systems, but this is the first CM3+ based carrier and one of the few RPi Compute Module based boards we can recall being promoted as an SBC. Like the Passepartout, the Pi-Tron CM3+ is aimed at industrial controller applications and runs Raspberry Pi OS (Raspbian Linux).

The 105.5 x 67mm Pi-Tron CM3+ is smaller than the Passepartout. You can choose from a variety of 1GB LPDDR2 equipped CM3+ options from zero eMMC (CM3+ Lite) to 32GB. Kontron adds 16-bit FRAM, and if you choose the CM3+ Lite, a microSD slot.

The Pi-Tron CM3+ is equipped with 2x 10/100 Ethernet and 2x USB 2.0 host ports. For media, you get a micro-HDMI 1.3a port for up to 1080p@30fps, as well as 2-lane MIPI-DSI with touchscreen support and a 2-lane MIPI-CSI interface.

Coastline terminal plug interfaces likely express the RS232, RS485, CAN, and 4x DIO (24 V/up to 800 mA) interfaces. The 40-pin GPIO connector is probably behind the other listed I/O: 2x UART, 2x I2C, 2x SPI, 28x GPIO, 2x PWM, and 4-bit SDIO. There is also a console debug interface.

The Pi-Tron CM3+ provides a 24VDC (±20 %) terminal plug input and consumes 2.4W to 9.6W when running without peripherals. Kontron touts the board’s “optimized passive cooling” at 0 to 55°C. There is also support for an RTC with battery.

PiXtend

Kontron’s PiXtend line of controller boards ship with CODESYS V3, as well as the CODESYS web visualization tool and Node-RED. The controllers offer industrial interfaces that comply with IEC 61131-3.

PiXtend V2 -L- and spec list
(click images to enlarge)

Kontron offers the PiXtend V2 -L- and smaller PiXtend V2 -S- controller boards plus an enclosed PiXtend eIO device that works with either. Based on the images, the default PiXtend V2 -L- is based on the Raspberry Pi 3 Model B+ while the PiXtend V2 -S- uses the earlier RPi 3 Model B. However, the specs for both controller boards list support for Pi models ranging from the RPi 1 to the RPi 4.

The RPi 3B+ SBC has a faster 1.4GHz clock rate for its quad -A53 block than the 1.2GHz Model B and adds USB-based GbE with PoE support and faster 802.11ac WiFi. Raspberry Pi recently announced it was cutting back on its 3B+ production in favor of the RPi 3 and CM3.

The PiXtend V2 boards are touted for their 64 Byte EEPROM for retaining memory of key data against power failure, as well as their ability to control and regulate short cycle times: 5ms at 200Hz for the -L- and 2.5ms at 400Hz for the -S-. Other highlighted features include “HighSide switches with separate feed and all-round protection,” including 12x HighSide on the -L-.

PiXtend V2 -S- and spec list
(click images to enlarge)

The 236.3 x 101.8 x 27mm PiXtend V2 -L- offers more I/O than the -S- model, including 16x DI, 12x DO, 6x analog inputs, 2x analog outputs, 4x GPIO, and 6x PWM/servo outputs. You also get CAN, RS232, and a Modbus RTU capable RS485 link, among other I/O shown in the chart farther above.

The 166.3 x 101.8 x 27mm PiXtend V2 -S- offers lesser amounts of I/O and lacks CAN support (see chart above). Like the -L-, the -S-provides a 24VDC input and a 0 to 50°C operating range.

The PiXtend eIO, which is also available in a board-level product, “acts as an ideal complement” to the PiXtend V2 boards, says Kontron. The device offers an RS485 bus that supports Modbus RTU “and our lean PiXtend eIO ASCII Protocol.”

PiXtend eIO and spec list
(click images to enlarge)

“Thanks to ultrafast HyperLogic, simple, logical links between inputs and outputs can be implemented by the modules themselves, eliminating the need to transmit data via the bus system,” says Kontron. “The digital inputs can be used to count events, meaning that this process does not have to be implemented via software.”

The device offers up/down and 2-channel counters independent of the bus cycle. Up to 32 devices can be operated as a single network/bus.

The PiXtend eIO is available in Digital One and Analog Models. In place of the 8x DO and 8x DI on the Digital One, the Analog One provides a variety of analog inputs and outputs, as shown in the chart above. The 106 x 105 x 45mm enclosed model has a 24VDC input and a 0 to 60°C range.

Further information

The Baseboard BL Pi-Tron CM3+ with CODESYS support and the PiXtend products appear to be available, with pricing undisclosed. More information may be found in Kontron’s Pi-Tron CM3+ CODESYS announcement and Pi-Tron CM3+ product page, as well as its PiXtend V2 -L-, PiXtend V2 -S- , and PiXtend eIO product pages.