direct J1708/J1939 connection

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Q: How does the tcp link work in FMB640?

A: TCP link mode works like a "tunnel" connecting RS232 device with the server. FMB640 simply acts like a "data tunnel".

Using TCP link mode, each time RS232 message is received, FMB640 would re-sent RS232 data to the server. This requires that FMB640 is connected to the server 24/7 and always has open data link with the server, because TCP link mode only works when device has open data link with the server.

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Q: Does FMB640 support modbus ?

A: FMB640, FM63 and FMB125 support RS485,  can support MODBUS. But functionality is not available, thus special development is required.

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