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Hi, I'm interested in purchasing a Trycom or ATC Ethernet / Serial converter. I would like to use it to connect to a satellite modem or ADSL router. These devices support the NAT functionality to allow the converters to be reachable from public IP addresses.
After properly configuring the IP part of the converters, can they support these types of connections or are there any contraindications or tricks to be used?
Our Ethernet-Serial Converters that we market can be reached from public IPs using the NAT functionality of the router.The management of the addressing of incoming connections is managed by the router which through an address translation (NAT) redirects all incoming requests to the IP public on a certain port, to a private IP inside the local network (The IP defined on the converter) .In this way, assuming that our site http://www.elsist.it there is a router that performs NAT from port 7000 to the converter address (Example 192.168.10.50, port 4000) The connection made from the Internet to our DNS (or static IP) on port 7000 would be redirected to the converter and the data received from this connection will be available on the serial output and vice versa.
Attention, it is necessary to verify that the ADSL or satellite service provider uses a public IP, even if it is not a static IP. Many ADSL, wireless, satellite routers manage the DynDNS service to let you know the dynamic IP assigned to them at the time of connection. Through this IP it will then be possible to use the NAT to reach the converter inside the network.
But some providers to make up for the lack of IP manage the network using NAT on the connected users, therefore the assigned IP is not public, but it is an IP internal to the provider's network. In this case it is not possible to reach the node from the outside.
To understand if your IP is accessible it is enough, knowing the IP assigned to the router at the time of connection, to perform a ping from another PC connected to the Internet and check if a response is returned.
I recently bought an ATC-2000 converter from you. I have performed a configuration like a TCP server (I could also send the configuration file) and connected a rs232 device (plc Mitsubishi).
At the same time I have installed VirCOM on a laptop and in the local network I can download programs and perform online operations. Then I unplugged the laptop from the LAN and I connected to the network with a key of "3". Before doing this I performed the router configuration (NAT and Firewall).
After a few attempts, the serial test operation is successful, but as soon as I try to download the program, the connection is interrupted. I tried to lower the transmission speeds, I tried to put the check mark on and off Speed control e On the fly but a few times the Test works and never complete transmission.
Then I also noticed that VirCOM does not always take the configured configurations.
Is there a working type configuration?Since from how you write me the converter on the ethernet network works allowing all the operations on the PLC as if it were connected directly to the serial port of the PC. I believe that the problem of not being able to operate with the PLC is to be found in the lengthening of the transmission times of TCP / IP packets.
Probably the PLC has a control over the delay times on the serial communication which causes it to drop the connection, so my advice is to check if the PLC has any time configuration parameters on the communication.
I bought an ATC-1000, it only works on the internal network, but I can't access through the router. I have configured the router to redirect to the static ip of the ATC. I use the virtual port as I do for the internal network but I don't get any response, I tried to ping and it's ok.
Do you have any suggestions?
The router must be configured to redirect access from the Internet on the router IP from a certain port to the ATC IP on the port defined in the parameter Port number.
Assuming that the ATC is configured as a TCP server and accepts connections on port 1000, we will have to configure the router so that incoming connections from the Internet on port 1000 are redirected to the IP of the ATC port 1000.
Remember that the port numbers can be any, and they can be different between the inbound port of the router and the port of the ATC. But if you use the same port number, you avoid having to change it when operating from inside the network and from outside. In practice, only the IP will have to be changed.
Another detail to keep in mind is the gateway address defined on the ATC which must be that of the router.
Then you must be sure that the provider offering the Internet service (Telecom, Fastweb, etc.) does not block the defined port, some providers block incoming access from the Internet on some ports for security.
I have recently purchased some ATC1000 units, but I am having some problems in use.
If in the tcp / ip telnet settings, I set the CLIENT option I lose control of the unit and I am forced to reset it with VCOM. I wonder what the DISABLE setting is for.
Also, strangely enough, when establishing a connection using Hyperterminal (or similar programs), a connection is established but it only lasts a few seconds. With some diagnostics, I get that the connection was rejected by the ATC1000 but I don't understand the reason. What I don't understand is why the connection is sometimes established and maintained. In such cases I am able to ship packages regularly.
Curiously, one of the times the connection was dropped was following the change in the serial transmission speed (from 57600 to 9600 baud). The problem exists in completely different contexts, even on different networks with different operators. Are there any forbidden 'sequences'?
What precautions should I take? The devices are used on LAN networks that go outside through routers with NAT service. There is no DHCP.
I also take this opportunity to ask you for clarification regarding the meaning of port 23 which is assigned by default. Actually I do everything through 80. What does the '23' represent?
Some questions are not clear to me, I try to answer logically, starting from port 23 assigned by default. Port 23 is the port to connect to from Hyperterminal in TCP / IP (See photos) or from any other program from which communication is to be managed. In practice, the data received from this connection will be sent to the serial output and vice versa.
Naturally, for the converter to be reachable from Hyperterminal (which acts as a TCP / IP client) it must be set in Server & Hosting. The mode Client it is used to connect to another converter, by defining Client the IP address of the converter to connect to is requested. In practice, two ATC-1000 converters work on the network by extending the serial line.
The option Disable, is used to disable the TCP / IP connection is used if you want to operate in UDP, of course you will need to enable UDP.
Port 80 is the HTTP server port and is used to manage the configuration web page, it is not used for data exchange.
Using the direct TC / IP connection without virtual COM, the only way to set the communication parameters is from the configuration web page.
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