p-net Profinet device stack

Web resources

Source repository: https://github.com/rtlabs-com/p-net
Documentation: https://rt-labs.com/docs/p-net
Continuous integration: https://travis-ci.com/rtlabs-com/p-net
rt-labs: https://rt-labs.com

p-net

The rt-labs Profinet stack p-net is used for Profinet device implementations. It is easy to use and provides a small footprint. It is especially well suited for embedded systems where resources are limited and efficiency is crucial.

It is written in C and can be run on bare-metal hardware, an RTOS such as rt-kernel, or on Linux. The main requirement is that the platform can send and receive raw Ethernet Layer 2 frames. The p-net stack is supplied with full sources including a porting layer.

Also C++ (any version) is supported.

rt-labs p-net is developed according to specification 2.3:

Conformance Class A (Class B upon request)
Real Time Class 1

Features:

TCP/IP
RT (real-time)
Address resolution
Parameterization
Process IO data exchange
Alarm handling
Configurable number of modules and sub-modules
Bare-metal or OS
Porting layer provided
Supports I&M0 - I&M4. The I&M data is supported for the device, but not for individual modules.

Limitations or not yet implemented:

Only a single Ethernet interface (no media redundancy)
No startup mode legacy
No support for RT_CLASS_UDP
No support for DHCP
No fast start-up
No MC multicast device-to-device
No iPar (parameter server) support
No support for time synchronization

This software is dual-licensed, with GPL version 3 and a commercial license. See LICENSE.md for more details.

Requirements

The platform must be able to send and receive raw Ethernet Layer 2 frames, and the Ethernet driver must be able to handle full size frames. It should also avoid copying data, for performance reasons.

cmake 3.13 or later

For Linux:

gcc 4.6 or later
See the "Real-time properties of Linux" page in the documentation on how to improve Linux timing

For rt-kernel:

Workbench 2017.1 or later

An example of microcontroller we have been using is the Infineon XMC4800, which has an ARM Cortex-M4 running at 144 MHz, with 2 MB Flash and 352 kB RAM. It runs rt-kernel, and we have tested it with 9 Profinet slots each having 8 digital inputs and 8 digital outputs (one bit each). The values are sent and received each millisecond (PLC watchdog setting 3 ms).

Dependencies

The p-net stack contains no third party components. Its external dependencies are:

C-library
An operating system (if used)

Tools used for building and documentation (not shipped in the resulting binaries):

cmake (BSD 3-clause License)
Sphinx (BSD license)

Contributions