INFICON STC-2002 Thin Film Deposition Controller Operating Manual - Manual (Page 154)

p STC-2002 DEPOSITION CONTROLLER y
SECTION 5.XX e page 152 of 276 ^
Terms and Definitions Table 5.1: Glossary Of Terms continues from previous page...
Edges
A condition that has to do with the instant in time of an event's occurrence. An example is the pushing of the zero key. The action
takes place on the edge of pushing the key. Edges are categorized by the direction of change in the associated state. Positive or
rising (Ç) and negative or falling (
↓) (True to False). See Sections x5.4, 5.5, and 5.6
ID Number
A code that the STC-2002 uses to refer to a state or event. It can be up to a 3 digit number. See Sections x5.3 (table 5.6) and 5.7
Token
Either the combination of an input/output (I/O) function and an ID number, or a Boolean, logical, arithmetic, or relational operator.
A token is made up of input or output functions with an ID number. An operator is also a token (not, or, and, etc.). See Section x5.8
Rung
A rung is a line of an I/O program. Each rung has a number associated with it. This term is a carryover from programmable logic
controllers (PLC). An I/O program is made up of rungs of tokens. Each rung has 1 or more input tokens, may contain operators, and
has 1 output token. See Sections x5.6, 5.7 and 5.8
Soft Node
A soft node is a special input / output variable in the STC-2002. It is a holding area where intermediate results can be stored. They
are not associated with any machine state. By using soft nodes, complex functions can be implemented such as counters and shift
registers. Soft nodes can also be scalars. See Section 5.7
Stack
The method that the STC-2002 uses to evaluate Boolean expressions. Each Boolean value is placed on a stack when an operator or
input expression is encountered and popped off when an output expression is encountered. By using a stack, parenthesis are not
needed in writing I/O programs. See Section 5.8
Push
Every time the STC-2002 comes across an input function, the associated value (T/F, On/Off) is pushed on the top of the stack.
Everything else in the stack moves down one position. See Section 5.8
Pop
Every time the STC-2002 comes across an output function or operator, the top value(s) is popped off of the stack (and another
pushed back in the case of operators). In the case of an output function, the value that is popped is used to define the specific output
behavior performed. See Section 5.8
Table 5.2: Glossary Of Terms.