Data Types Applicaton Layer The Siemens Milltronics SmartLinx instrument parameters take on many values in various formats, as discussed in the Siemens Milltronics SmartLinx instrument manual. For the convenience of the programmer, those values are converted to and from 16-bit integer numbers, since those are easily handled by most PLCs. Integer Level Products Integer parameter values are by far the most common. For example, parameter P920 (Reading) returns a number representing the current reading (either level or volume, depending on the Siemens Milltronics SmartLinx instrument configuration).
Numeric values may be requested or set in units or percent of span, and may be specified with a number of decimal places. Numeric values must be in the range -20,000 to be +20,000 to be valid. If a parameter is requested and its value is more than +20,000, the number 32,767 is returned; if it is less than -20,000, the number -32,768 is returned. If this happens, increase the number of decimal places for that parameter. If a parameter cannot be expressed in terms of percent (e.g. span), or has no meaningful value, the special number 22,222 is returned.
Try requesting the parameter in units, or refer to the Siemens Milltronics SmartLinx instrument manual to understand the format and use of the requested parameter. Mass Dynamics Products Integers used on the Mass Dynamics products can have any valid value. So, the entire range from -32,768 to 32,767 or 0 to 65,535 is available and no values are used as error conditions. Bit Values Bits are packed into registers in groups of 16 bits (1 word). In this manual bits are numbered from 00 to 15, with bit 00 referring to the least significant bit and bit 15 referring to the most significant bit.
MSB LSB Page 42 SmartLinx DeviceNet – INSTRUCTION MANUAL 7ML19981BH02 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00