User`s guide

Digital I/O
Adept controllers can communicate in a digital fashion with external devices using the Digital
I/O capability. Digital input reads the status of a signal controlled by user-installed
equipment. A typical digital input operation is to wait for a microswitch on a workcell
conveyor to close, indicating that an assembly is in the proper place. The WAIT instruction
and SIG function are used to halt program execution until a digital input channel signal
achieves a specified state. The program line:
WAIT SIG(1001)
halts program execution until a switching device attached to digital input channel 1001 is
closed. If signal 1002 is a sensor indicating a part feeder is empty, the code:
IF SIG(1002) THEN
CALL service.feeder()
END
checks the sensor state and calls a routine to service the feeder if the sensor is on.
The SIGNAL instruction is used for digital output. In the above example, the conveyor belt
may need to be stopped after digital input signal 1001 signals that a part is in place. The
instruction:
SIGNAL(-33)
turns off digital output signal 33, causing the conveyor belt connected to signal 33 to stop.
When processing on the part is finished and the part needs to be moved out of the work area,
the instruction:
SIGNAL(33)
turns the conveyor belt back on. The digital I/O channels must be installed before they can
be accessed by the SIG function or SIGNAL instruction. The SIG.INS function returns an
indication of whether a given signal number is available. The code line:
IF SIG.INS(33) THEN
can be used to ensure that a digital signal is available before you attempt to access it. The
monitor command IO displays the status of all digital I/O channels. For details on installing
digital I/O hardware, see the Adept SmartController User's Guide or the Adept MV Controller
User's Guide .
Digital output channels are numbered from 1 to 512. Input channels are in the range 1001
to 1512. Multiple signals can be turned ON or OFF with a single instruction.
SIGNAL(33),(-34),(35)
or
SIGNAL(-33),(34),(-35)
Digital I/O
(Undefined variable: Primary.Product_Name_V)Language User's Guide, version
17.x
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