Serial Comm PLC


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I need to connect a plc comm port to a device that only communicates at 115200 bps. The plc has max 19200. Anyone know of a device, possibly in the modulation/demodulation realm, that I can find that would help with this issue?
It is hard to believe that the device is not capable of operating at other baud rates. You would need a device that buffers data and than allows each side (one at one speed the other at another speed) to pack/read the buffer at its own baud rate. Otherwise I would look really hard at the port settings for each device. In the years I have been doing this I have yet seen a device which was fixed at a single baud rate.

A demod/mod device would not solve the problem. You may also want to check to see if the device will auto-connect at a different baud rate. Some devices may have a upper baud rate of 115.2K, but will connect at lower speeds - like a modem will automatically reduce the baud rate based upon line conditions.
What protocol is the PLC using? Does your 115.2K device use the same protocol?

Equustek offers DF1 to DF1 and Modbus to Modbus, as well as DF1 to Modbus converters to connect devices that use different baud rates/error checking schemes or protocols.
Check out the DL4000 product line at

We also are very quick at providing custom solutions using the DL4000 platform to handle many other serial protocols.

B&B electronics makes a serial protocol convertor which gives you full control over two com ports w/ 16k buffer.

Curt Wuollet

Anything programmable with two serial ports could do the speed translation. But I'm also curious what would only work at the often unreliable 115.2k with the limitations that imposes.