AW00123402000 Physical Interface
Basler ace USB 3.0 79
5.13 Checking the Status of the I/O Lines
5.13.1 Checking the Status of an I/O Line
You can determine the current status of any I/O line that depends on whether an electrical signal is
applied to the line and whether the line inverter is disabled or enabled. In addition, factory settings
determine fundamentally whether a given electrical signal level will be considered to correspond to
a "high" or "low" line status.
For example, consider output line Line 2:
When no electrical signal (output signal) is applied and when the line inverter is disabled, the
signal level will be "high" according to factory settings and the LineStatus parameter value will
be "true" (see Table 16).
When an electrical signal is applied and when the line inverter is disabled, the signal level will
be "low" and the LineStatus parameter value will be "false".
When no electrical signal is applied and when the line inverter is enabled, the signal level will
be "low" and the LineStatus parameter value will be "false" (see Table 17)
When an electrical signal is applied and when the line inverter is enabled, the signal level will
be "high" and the LineStatus parameter value will be "true"
The signal levels and corresponding LineStatus parameter values for all I/O lines are listed below,
depending on whether an electrical signal is applied (as indicated by electrical signal level) and
whether line inverters are enabled (Table 16 through Table 19). Note that certain combinations of
electrical signal levels and line inverter settings result in identical line status (compare Table 16 and
Table 19 on one hand and Table 17 and Table 18 on the other).
No electrical signal applied and line inverters disabled:
The line status of a GPIO line (Line3, Line 4) does not depend on the configuration
of the GPIO line for input or output.
I/O Line Electrical Signal /
Electrical Signal
Level
Logical LineStatus
Parameter Value
Binary Expression
of the Line Status
Parameter Value
Line 1 (input) Off/Low False 0
Line 2 (output) Off/Low True 1
Line 3 (input/output) Off/Low True 1
Line 4 (input/output) Off/Low True 1
Table 16: I/O Lines and Line Status With no Electrical Signals Applied and All Line Inverters Disabled