ZeroCrossUp
The block produces an output event if the input crosses zero with a positive slope. The block does not react to jumps across zero due to events so an input may change sign without any even generation (in particular if the input is a discrete signal). For detecting discrete-time zero-crossings, use the EdgeTrigger block.
![]()
Library
Activate/ActivationOperations
Description
The ZeroCrossUp block produces an output event if the input crosses zero with a positive slope. The block does not react to jumps across zero due to events so an input may change sign without any even generation (in particular if the input is a discrete signal). For detecting discrete-time zero-crossings, use the EdgeTrigger block.
The input should be of type double.
Parameters

| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
dept | Always active | Status of the crossing behavior. Default is off. | Scalar | 0 |
Ports
| Name | Type | Description | IO Type | Number |
|---|---|---|---|---|
Port 1 | explicit | input | 1 | |
Port 2 | activation | output | 1 |
Advanced Properties
| Name | Value | Description |
|---|---|---|
always active | no | |
direct-feedthrough | no | |
zero-crossing | yes | |
mode | no | |
continuous-time state | no | |
discrete-time state | no |