Digital Output

Gocator sensors can convert measurement decisions or software commands to digital output pulses, which can then be used to output to a PLC or to control external devices, such as indicator lights or air ejectors.

Digital outputs cannot be used when taking scans using the Snapshot button, which takes a single scan and is typically used to test measurement tool settings. Digital outputs can only be used when a sensor is running, taking a continuous series of scans.

A digital output can act as a measurement valid signal to allow external devices to synchronize to the timing at which measurement results are output. In this mode, the sensor outputs a digital pulse when a measurement result is ready.

A digital output can also act as a strobe signal to allow external devices to synchronize to the timing at which the sensor exposes. In this mode, the sensor outputs a digital pulse when the sensor exposes.

Each sensor supports two digital output channels. See Digital Outputs for information on wiring digital outputs to external devices.

Trigger conditions and pulse width are then configured within the panel.

To output measurement decisions

1. Go to the Output page.
2. Click Digital 1 or Digital 2 in the Output panel.
3. Set Trigger Event to Measurement.
4. In Configuration, set Assert On and select the measurements that should be combined to determine the output.

If multiple measurement decisions are selected and Assert On is set to Pass, the output is activated when all selected measurements pass.

If Assert On is set to Fail, the output is activated when any one of the selected measurements fails.
5. Set the Signal option.

The signal type specifies whether the digital output is a continuous signal or a pulsed signal. If Signal is set to Continuous, the signal state is maintained until the next transition occurs. If Signal is set to is Pulsed, you must specify the pulse width and how it is scheduled.
6. Specify a pulse width using the slider.

The pulse width is the duration of the digital output pulse, in microseconds.
7. Check the Scheduled option if the output needs to be scheduled; otherwise, leave it unchecked for immediate output.

A scheduled output becomes active after the delay from the start of Gocator exposure. A scheduled output can be used to track the decisions for multiple objects as these objects travel from the sensor to the eject gates.

The Delay setting specifies the distance from the sensor to the eject gates.

An immediate output becomes active as soon as measurement results are available. The output activates after the sensor finishes processing the data. As a result, the time between the start of sensor exposure and output activates can vary and is dependent on the processing latency. The latency is reported in the dashboard and in the health messages.
8. If you checked Scheduled, specify a delay and a delay domain.

The Delay specifies the time or encoder distance between the start of sensor exposure and when the output becomes active. The delay should be larger than the time needed to process the data inside the sensor. It should be set to a value that is larger than the processing latency reported in the dashboard or in the health messages.

The unit of the delay is configured with the Delay Domain setting.
9. If you want to invert the output signal, check Invert Output Signal.

To output a measurement valid signal

1. Go to the Output page.
2. Click on Digital 1 or Digital 2 in the Output panel.
3. Set Trigger Event to Measurement.
4. In Configuration, set Assert On to Always.
5. Select the measurements.

The output activates when the selected decisions produce results. The output activates only once for each frame even if multiple decision sources are selected.
6. Specify a pulse width using the slider.

The pulse width determines the duration of the digital output pulse, in microseconds.

To respond to software scheduled commands

1. Go to the Output page.
2. Click Digital 1 or Digital 2 in the Output panel.
3. Set Trigger Event to Software.
4. Specify a Signal type.

The signal type specifies whether the digital output is a continuous signal or a pulsed signal. If the signal is continuous, its state is maintained until the next transition occurs. If the signal is pulsed, user specifies the pulse width and the delay.
5. Specify a Pulse Width.

The pulse width determines the duration of the digital output pulse, in microseconds.
6. Specify if the output is immediate or scheduled.

A pulsed signal can become active immediately or be scheduled. A continuous signal always becomes active immediately.

Immediate output becomes active as soon as a scheduled digital output (Schedule Digital Output) is received.

Scheduled output becomes active at a specific target time or position, given by the Scheduled Digital Output command. Commands that schedule an event in the past will be ignored. An encoder value is in the future if the value will be reached by moving in the forward direction (the direction that encoder calibration was performed in).

To output an exposure signal

1. Go to the Output page.
2. Click Digital 1 or Digital 2 in the Output panel.
3. Set Trigger Event to Exposure Begin or Exposure End.
4. Set the Pulse Width option.

The pulse width determines the duration of the digital output pulse, in microseconds.

To output an alignment signal

1. Go to the Output page.
2. Click Digital 1 or Digital 2 in the Output panel.
3. Set Trigger Event to Alignment.

The digital output state is High if the sensor is aligned, and Low if not aligned. Whether the sensor is running does not affect the output.

To respond to exposure begin/end:

1. Go to the Output page.
2. Click Digital 1 or Digital 2 in the Output panel.
3. Set Trigger Event to Exposure Begin or Exposure End.

You can use a Gocator's part detection capabilities as a digital output trigger. This lets you use the sensor as a photo-eye, eliminating the cost of installing a separate photo-eye. In this mode, the digital output goes high and is held high if the part detection logic is currently tracking at least one part. If part detection starts tracking a second part or more, the output stays high. After the part detection parts tracked counter returns to zero, the output goes low again.

Make sure you properly configure and test part detection. For more information, see Part Detection.

To respond to a part detection

1. Go to the Output page.
2. Click Digital 1 or Digital 2 in the Output panel.
3. Set Trigger Event to Part Detection.