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 or Daniels devices as well, was created to assist in communicating with devices which use Enron or Daniels style Modbus for reading and writing floating point values. While floating point values can be read or written in standard modbus devices with out the need to enable this mode, most Enron or Daniels devices are programmed such that, when reading their floating point data (commonly in the 7001 and above range) the count field is assumed to be the number of floats to be read or written, not the number of registers as usual. This means that if you Attempt to read from 7001 with a count of 2, you would actually get 4 registers returned (two 32 bit floating values) instead of the usual two 16 bit registers. Many of our products can actually read Enron or Daniels floating points with out even enabling the mode because even if we ask for 4 registers, and they return us 8, will we take what they give us rather then rejecting the message. However, when writing to an Enron or Daniels devices, the mode is almost always essential, as most Enron or Daniels devices will reject our write attempt if we tell them to expect 2, and only give them 2 registers instead of 4.
For further details about how our Enron-Daniels mode is used, please refer to your product's user manual and be aware that depending on the age of your product and when its manual was last updated, this mode may be referred to as Float Flag, but other then the name difference, should function identical to how it is described.