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How do I get Floating-Point values in a PLC5 or SLC processor from the Modbus module?

To view the floating-point value, the two 16-bit integers must be copied to a floating-point variable in the processor. For PLC and SLC processor, a COP command is used, with the source being the first integer value location, the dest being the F file location, and the len being ...

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What causes a conditional command to be issued?

A conditional command is useful when the same value does not need to be written to the end device continuously, but rather on change. A conditional write command is scanned based upon its poll rate (like all other commands).  The difference is that it will not be execut...

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What does a -36 modbus error code indicate?

A negative thirty six (-36) error code is generated when we have successfully connected to a device and issued the device a Modbus request, but it has not responded to the request within the defined response time out period. This is akin to calling some one on the phone, having s...

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What is Enron-Daniels mode?

In some of our older Modbus products we had/have a feature called float flag. This feature, which has been renamed to Enron-Daniels mode in most of our newer Modbus products to avoid the misconception that this mode was necessary for accessing floating point values in non-Enron o...

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