Counter

The Counter operation maintains an unsigned integer counter with Up, Down, and Reset inputs. It supports an optional maximum value; when the limit is reached the counter wraps to 0 (overflow) or to the maximum (underflow), signalling the event on dedicated outputs. It includes gate control to conditionally skip counting.

With neither Up nor Down connected the count never moves, and the Editor flags the Node with a warning frame.

Inputs

Port	Type	Required	Description
> (Gate)	Any	No	When connected, a false or Nil value stops the path. See Gate Inputs.
Up	Any	No	When truthy, increments the counter by 1.
Down	Any	No	When truthy, decrements the counter by 1.
Reset	Any	No	When truthy, resets the counter to 0 (takes precedence).

Outputs

Port	Type	Default	Description
Count	Integer	0	Current counter value.
Overflow	Boolean	false	true for one cycle when an increment wraps the counter from its upper limit to 0.
Underflow	Boolean	false	true for one cycle when a decrement wraps the counter from 0 to its upper limit.

Properties

Name	Type	Default	Description
Counter Limit	StackedDataSet		Controls the counter’s upper bound:
Integer Value	Integer	100	Maximum value (min 1). When exceeded the counter wraps to 0. If this sub-type is not selected, the counter runs up to 2 147 483 647.
On Error	Combo	Stop this branch	Per-op On Error verb (Stop this branch / Continue with the last value / Continue with the fallback). See the Error Handling guide.

State on Reload

Counter value and all outputs are preserved across restarts within the configured time window. There is no compatibility check on reload: if the Limit Mode or Max Value changed, the restored counter may be outside the new range and will trigger overflow on the next count-up. Review the counter value after reconfiguration.

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How It Works

1. Gate check — If a Gate input is connected, evaluate it. A false or Nil value stops the execution path; outputs keep their previous values.

2. Reset check — If Reset is truthy, the counter is set to 0 and both Overflow/Underflow are cleared. Processing stops.

3. Up / Down — If Reset is not active, Up and Down are evaluated in order. Both may fire in the same cycle (net effect may cancel out, but overflow/underflow can still trigger).

4. Wrap-around — If a configured Counter Limit is set:

   • Incrementing past the limit wraps to 0 and sets Overflow to true.
   • Decrementing below 0 wraps to the limit and sets Underflow to true.

5. Output — The current counter value and overflow/underflow flags are written.

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Examples

Data format

All inputs and outputs use MessagePack internally. The examples below show values in JSON notation for readability.

Basic Increment

Counter Limit: No max value

Up: true   Down: false   Reset: false

Starting from 0, the counter becomes 1.

Output	Value
Count	1
Overflow	false
Underflow	false

Overflow

Counter Limit: 10   Current count: 10

Up: true   Down: false   Reset: false

The counter wraps from 10 to 0.

Output	Value
Count	0
Overflow	true
Underflow	false

Underflow

Counter Limit: 10   Current count: 0

Up: false   Down: true   Reset: false

The counter wraps from 0 to 10.

Output	Value
Count	10
Overflow	false
Underflow	true

Reset

Current count: 123

Up: false   Down: false   Reset: true

Output	Value
Count	0
Overflow	false
Underflow	false

Gate Block

Gate: false   Current count: 5

The gate is closed. All outputs keep their previous values and the execution path stops at this Node.

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Use Cases

• Tracking events (messages processed, successful operations)
• Implementing iteration counters
• Managing resource limits or quotas with wrap-around behaviour

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Limitations

• Counter range is 0 to 2 147 483 647.
• Only unit increments/decrements; larger steps require multiple trigger events or external logic.