Manualshelf

Hardware manual

ManualsBrandsDatalogic ManualsComputer equipmentA20
241242243244245246247248249250
Impact Reference Guide Communication Drawer
3-187 Datalogic Automation Inc.
This sets the upper and lower thresholds automatically based on all the grey levels in the ROI. The lower
threshold is set to 0%, and the upper threshold is set to a value somewhere in the valley between the bright
pixel and the dark pixel peaks. The exact value depends on the statistics of the two peaks. Dark pixels are
thus considered in-range. This setting is best used when looking for a bright part of an image with non-uni-
form grey levels. In this example, the lower threshold would be 0% and the upper threshold approximately
50%.
Block Adaptive Threshold
The tool breaks the ROI into 16 blocks from left to right and calculates a separate threshold in each block
using the Adaptive Threshold method.
Fixed Threshold - Dark or Light Characters
This sets the upper and lower thresholds based on the Fixed Threshold Range input value. Pixels with grey
level values between the thresholds are considered in-range. This setting is best used for an image with uni-
form grey levels.
Communication Drawer
Discrete Input
In the Communication Drawer
The Discrete Input tool reads the Impact device’s polled input lines. The input lines are read only when the
tool executes. Event inputs are configured in the Events list in the main task section (see“VPM Task Config-
uration” on page 3-34).
The state of the inputs (On or Off) can be interpreted as an integer value or as a Binary Coded Decimal
(BCD) value. When Interpret as BCD is True, and the four inputs produce an illegal BCD value, the output
values associated with the Inputs are still set, but Current State is not updated and BCD Output Valid is set to
false.
A Setup is available for this tool. See “How to set up the Discrete Input tool” on page 3-188 for more details.
Input Name What it is
Interpret as BCD If True, the input values are read as Binary Coded Decimal (BCD)
Output Name What it is
Current State The binary value of all inputs (displayed as integer)
Threshold
Range
Lower
Threshold
Upper
Threshold
0 100