Trouble with Ethernet Communications?
- You Cannot get Reliable Communications with a Logger over Ethernet
- Ethernet drops out after a few seconds
- Message from VT Setup or VT Collect is: Connection is forcefully rejected
- Message from VT Setup or VT Collect is: No route to Host
- The eLVT box is found by the Lantronix software and it can connect in VT setup, but you can not get any data from the eLVT
You Cannot get Reliable Communications with an eLVT over Ethernet
Check with Hyperterminal that you can talk to the module and request the Hardware Type.
Using Hyperterminal to talk to an eLVT module
Load the Windows Hyperterminal program (c:/program files/accessories/hypterterminal/hypertrm.exe) and set up the communications as follows:
Connect To tab
Connect using:
Direct to COMx
(where x is the port number to which your
eLVT is connected.)
Configure ...:
Bits per second 9600
Data bits 8
Parity None
Stop Bits 1
Flow Control None
Settings tab
Ascii Setup ...:
Ascii Sending
Echo characters typed locally - Checked
others as default
Ascii Receiving
Default settings
You should now be able to communicate with a module over the serial link created. To request the hardware type you need to know the address of the module with which you are trying to communicate. The default address for a single eLVT module is 0. (You can check and change the module address using the VT Setup program.)
Using Hyperterminal to read the hardware type for a module with address x you need to type:
*x DCO HT (and press Enter) the reply will be: x: ML825 (possibly followed by another letter) e.g. for address 0 you send *0 DCO HT and get back 0: ML825
You will not get a reply if:
- There is no communications link between the PC and the eLVT - check the cable(s)
- You have sent the wrong address - check with the VT Setup software
- The eLVT is not powered
Did you get back the correct reply?
- No: You need to check the setup of the Device Installer virtual COM port and the Ethernet connection.
Use the Device Installer program to check the setup.
Use the Search button to get a list of eLVT units (and any other devices) on your local network.
"Ping" the eLVT unit to confirm that there is a network connection to it: click the Ping button and enter the IP address of the eLVT unit you want to check. The response time for communications with a locally connected eLVT unit will typically be 0 msecs. - Yes: Wait 10 seconds then repeat the steps to Request the Hardware Type. Did you still get back the correct reply? If not your LAN is probably routing your messages out to a WAN, as well as to the eLVT. Check the GATEWAY setting with your network manager.
Ethernet drops out after a few seconds
This is often due to the network having internet access. Requests to eLVT units are also routed out to the internet, and after a few seconds an Error 404 is returned which disrupts the messages between the PC and the eLVTs.
Message from VT Setup or VT Collect is Connection is forcefully rejected
-
eLVT is on a different sub-net to the PC:
Run the Device Installer software and check your PC and the eLVT are both on the same sub-net. -
The serial server in the eLVT has lost its factory settings, particularly
the local port and internal baud rate.
Run the Device Installer software and check the setting for LOCAL PORT and PORT 1 BAUD RATE.
Message from VT Setup or VT Collect is No route to Host
Check the power supply to the box. It must be a 12 V DC supply. The Ethernet circuit runs off 3.3 V but the rest of the circuit requires the full 12 V, so it is possible for the Ethernet to be working but not possible for request for information to get through the Logger section.
The eLVT box is found by the Lantronix software and it can connect in VT setup, but you can not get any data from the eLVT
Back: Fault Finding.