GRASS VALLEY NV9640, User Manual

Page: 87 / 112

77
NV9640
User’s Guide
Configuring Outputs
Clicking an output button (one of 4) displays a “Relay Rule” dialog for the output:
Fig. 6-4: Relay Rule Dialog
In this dialog, you create a Boolean expression involving sources destinations, port status, and
GPI (input) status. When the conditions of the Boolean expression are met (i.e., the expression is
“true”) the relay closes. When the conditions are not met, the relay opens. Figure 6-4 shows one
such Boolean expression.
Boolean expressions comprise terms and operators . The operators include those indicated on
the left: AND, OR, and NOT. Expressions can be parenthesized to control the order of evaluation.
Operator precedence is normally NOT > AND > OR. All parenthesized expressions are evaluated
first; expressions in nested parentheses are evaluated before those in outer parentheses.
Terms (i.e., operands) are generated by choosing entries in the other fields in this dialog and
clicking ‘ADD’. The example shows the following:
Dest. Device: MON2 Dest. Level:SD
Source Device: CAM1 Source Level:SD
Choosing these items (and clicking ADD) produces the Boolean sub-expression:
SD on CAM1 is switched to SD on MON2
In Figure 6-4, that sub-expression is ANDed with another sub-expression
INPUT 3 OR INPUT 8
The relay will turn on when the entire expression is true. That is, when the switch occurs and
either of the inputs (3 or 8) transitions from off to on.
term
operator
term
operator
term