Script Operands

A local variable is a lower-case letter name. _ and digits (except as first characters) can also be used as a part of the name. The name can consist up to 30 characters.

A global variable is a variable that all Neuron scripts can use and must be defined in global variables setup environment. When starting the Neuron program, the variable gets the value 0. When the Neuron program ends, all global variables are disconnected, so next time the Neuron program starts, all its global variables are 0 again. To save data until next execution time, data base variables should be used.

A global variable starts with the upper-case letter G followed by a dot and a lower-case letter name. _ and digits (except as first characters) can also be used as a part of the name. The name can consist up to 20 characters (except the leading G.).

An object variable is the attribute of object. It can be used thought all the Neuron subroutines. When starting the Neuron instance, the variable gets the previous value. When the Neuron instance ends, all tag variables are saved on the hard disk for next start.

An object variable consists of three elements. The first element is the object name. For example, temperature object can use "SENSORA" as its object name. humidity object can use "SENSORB" as its object name.

Second, there is a constant inside [] called object index which can be a local variable. This number represents the item index of the objects.

Therefore, the actual temperature of temperature object would be SENSORA[ix].TEMPERATURE. This is the object variable.

A constant is numeric value in the range -2,147,483,648 to 2,147,483,647. The constant can be a signed decimal (as above), unsigned hexadecimal in case of a leading 0x (0x0 to 0xffffffff) or unsigned octal in case of a leading 0 (0 to 037777777777). A constant with decimal place is also accepted as a double value in script. For example, pi is 3.1415. Script constant supports two value type.

In the system, there are some system global variables that are used by the system. A system global variable is a global variable, with its syntax. The variables are prepared/used every time before starting the main program.