SDM-SIO4 User Guide

5.1.5 Parameter 7 — Values per Rep

This determines how many values to send or receive, starting from the specified input location (parameter 8). Data can be either 4-byte floating point values or single bytes, determined by the SDM-SIO4 command number.

Some commands require no input or output of values; for these commands this parameter would be set to zero.

5.1.6 Parameter 8 — Starting Input Location

This is the first input location that values will be sent from or written to consecutively until all values per rep (parameter 7) are done.

5.1.7 Parameters 9 and 10 — Multiplier and Offset

The multiplier and offset are applied to all incoming and outgoing data.

NOTE The multiplier should normally be set to 1.000; if left at 0.000 then zero value data will be stored.

5.2 Commands and Options (Parameters 4, 5 and 6)

For many of the command options listed below, it is necessary to leave a small delay before calling another instance of the instruction which communicates with the SDM-SIO4. This is required to allow the SDM-SIO4 to process the instructions it has been given. Failure to allow these delays will probably cause the SDM-SIO4 to return invalid data. The delays are called ‘Minimum delay’ in the command descriptions.

Many of the delays vary with the parameters of the instruction, in which case a formula is quoted to enable you to calculate the delay. All delays are in milliseconds. The notation used in the formula is:

floats is number of locations to convert.

characters is the number of characters to each float value including decimal point and sign.

ports is the number of ports the value or values are being transmitted from. This is 1 if parameter 3 in P113 is 1..4 or 4 if parameter 3 is 5.

NOTE The delay required in the program can either be forced using Instruction P22, or by using the time to execute other measurement or processing instructions.

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Campbell Hausfeld SDM-SIO4 manual Commands and Options Parameters 4, 5, Parameter 7 Values per Rep