February-12th-2018, 03:53 PM
Hello Vincent,
if you have read netPI and netHAT cannot support PLC master functionality this was in relation to the type of industrial network chips both units support. Both units use netX chips that can only be loaded with industrial network slave protocols. And for a PLC you usually need a master protocol functionality with accurate timings. Only chips like our netX100 chip support an embedded master stack. But since more and more protocols are Ethernet based, that are not physically bound to a specific hardware like Profibus and CAN, more and more software protocols stacks are coming to the market. So yes netPI can also be a PLC and master if standard ethernet is the precondition.
So if you do not have specific protocol requirements in terms of timings and accuracy like Modbus TCP of course netX slave chips can be standard TCP/IP protocol stack supporting chips as well. So in this case netPI RTE 3 has one ethernet port coming from the Raspberry CPU and two additional standard ethernet ports supported by the netX CPU.
You have found that netPI supports EtherNet/IP as slave protocol. This is correct. But as a slave only and the whole protocol stack is handled in netX. Even high loads can be handled a normal Raspberry CPU can't. So with netPI we are in the same status as your WAGO IO. netPI and WAGO needs an EtherNet/IP master both to exchange process data with units such as PLCs from Allen Bradley.
But back to your focus ... Modbus TCP. In order to support Modbus TCP on netPI you have two possibilties.
1.) Install containerized Node-RED on your netPI. Then use the function embedded in Node-RED to install additional nodes. With this option install the Node-RED Node Modbus TCP https://flows.nodered.org/node/node-red-contrib-modbus and you have netPI supporting Modbus TCP in some minutes over Node-RED. The best of Node-RED is, once you have the data in Node-RED you can spread it around to nearly everywhere with one of the other 1500 pissible nodes. Unfortunately I have not found any EtherNet/IP master supporting node-red node.
2.) Install containerized CODESYS SoftPLC for raspberry on your netPI. CODESYS has immediate support for Modbus TCP Master and EtherNet/IP Master and PROFINET master over standard TCP/IP ethernet ports. A license per device costs you just $50 as far as I know. You can try it unlicensed for two hours before it stops operating. For testing this is excellent.
To your question about MQTT. You can install a mosquitto MQTT broker in separate a container on netPI. And Node-RED by default supports MQTT client functionality. We made a mosquitto MQTT broker example container for netPI already here https://hub.docker.com/r/hilschernetpi/n...tt-broker/
To your question how to make two ethernet ports of netX to standard ethernet ports just look to this example container https://hub.docker.com/r/hilschernetpi/n...ernet-lan/. Please consider that only one container in general can take control of netX at a time. Installing multiple container that all want to take control of the single netX resource will fail. Please consider also that all examples related to netX are made for netPI and not for netHAT. netHAT always needs different software binaries than netPI.
So If I was you I would do the following:
Build a single container (on your Raspberry Pi 3, I do it at home too):
* take parts of the source code of https://hub.docker.com/r/hilschernetpi/n...ernet-lan/ to make netX to standard ethernet ports
* install node-red into this container as shown in source code in the container example https://hub.docker.com/r/hilschernetpi/n...-fieldbus/. But do not install the netX Node-RED nodes please...cause netX shall be standard ethernet interface and not loaded with real-time ethernet slave protocols.
* install https://flows.nodered.org/node/node-red-contrib-modbus into your node-red as nodes
Then you are happy and have everything you need.
At home I do it the same on my raspberry (now netPI). I have containerized Node-RED and instead of Modbus TCP I am using CUL http://busware.de/tiki-index.php?page=CUL for wireless connectivity to my IOs.
Thx
Armin
if you have read netPI and netHAT cannot support PLC master functionality this was in relation to the type of industrial network chips both units support. Both units use netX chips that can only be loaded with industrial network slave protocols. And for a PLC you usually need a master protocol functionality with accurate timings. Only chips like our netX100 chip support an embedded master stack. But since more and more protocols are Ethernet based, that are not physically bound to a specific hardware like Profibus and CAN, more and more software protocols stacks are coming to the market. So yes netPI can also be a PLC and master if standard ethernet is the precondition.
So if you do not have specific protocol requirements in terms of timings and accuracy like Modbus TCP of course netX slave chips can be standard TCP/IP protocol stack supporting chips as well. So in this case netPI RTE 3 has one ethernet port coming from the Raspberry CPU and two additional standard ethernet ports supported by the netX CPU.
You have found that netPI supports EtherNet/IP as slave protocol. This is correct. But as a slave only and the whole protocol stack is handled in netX. Even high loads can be handled a normal Raspberry CPU can't. So with netPI we are in the same status as your WAGO IO. netPI and WAGO needs an EtherNet/IP master both to exchange process data with units such as PLCs from Allen Bradley.
But back to your focus ... Modbus TCP. In order to support Modbus TCP on netPI you have two possibilties.
1.) Install containerized Node-RED on your netPI. Then use the function embedded in Node-RED to install additional nodes. With this option install the Node-RED Node Modbus TCP https://flows.nodered.org/node/node-red-contrib-modbus and you have netPI supporting Modbus TCP in some minutes over Node-RED. The best of Node-RED is, once you have the data in Node-RED you can spread it around to nearly everywhere with one of the other 1500 pissible nodes. Unfortunately I have not found any EtherNet/IP master supporting node-red node.
2.) Install containerized CODESYS SoftPLC for raspberry on your netPI. CODESYS has immediate support for Modbus TCP Master and EtherNet/IP Master and PROFINET master over standard TCP/IP ethernet ports. A license per device costs you just $50 as far as I know. You can try it unlicensed for two hours before it stops operating. For testing this is excellent.
To your question about MQTT. You can install a mosquitto MQTT broker in separate a container on netPI. And Node-RED by default supports MQTT client functionality. We made a mosquitto MQTT broker example container for netPI already here https://hub.docker.com/r/hilschernetpi/n...tt-broker/
To your question how to make two ethernet ports of netX to standard ethernet ports just look to this example container https://hub.docker.com/r/hilschernetpi/n...ernet-lan/. Please consider that only one container in general can take control of netX at a time. Installing multiple container that all want to take control of the single netX resource will fail. Please consider also that all examples related to netX are made for netPI and not for netHAT. netHAT always needs different software binaries than netPI.
So If I was you I would do the following:
Build a single container (on your Raspberry Pi 3, I do it at home too):
* take parts of the source code of https://hub.docker.com/r/hilschernetpi/n...ernet-lan/ to make netX to standard ethernet ports
* install node-red into this container as shown in source code in the container example https://hub.docker.com/r/hilschernetpi/n...-fieldbus/. But do not install the netX Node-RED nodes please...cause netX shall be standard ethernet interface and not loaded with real-time ethernet slave protocols.
* install https://flows.nodered.org/node/node-red-contrib-modbus into your node-red as nodes
Then you are happy and have everything you need.
At home I do it the same on my raspberry (now netPI). I have containerized Node-RED and instead of Modbus TCP I am using CUL http://busware.de/tiki-index.php?page=CUL for wireless connectivity to my IOs.
Thx
Armin
„You never fail until you stop trying.“, Albert Einstein (1879 - 1955)
