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OP5142EX1 Event Detector




The OP5142EX1 Event Detector block is used to return information describing rising-edge and falling-edge transitions (or events) occurring on digital input channels of an OP525x carrier connected to an OP5142 board.

Each transition is described by the ending state of the digital line (0 for a falling edge, and 1 for a rising edge), and the time, relative to the beginning of the calculation step, when the transition occurred.

The data values are transferred from the OP5142 bitstream to the RT-LAB model through one DataOut port of the bitstream, via the PCIe bus of the target computer.

Each OP5142 bitstream using digital input channels in Event Detector mode comes with a configuration file which lists the Data port number and the corresponding OP525x location in the system. The configuration file name is the same as the bitstream file name entered in the OpCtrl OP5142EX1 block, with the extension .conf instead of .bin.

This configuration file uses three parameters to describe the location of the OP525x channels:

  • the Slot number (in the range 1 to 4) is the slot of the backplane connected to the OP5142 in which the OP5251 is installed,
  • the Section A or B is a subset of 32 lines of the OP525x carrier. For example, with the 32 In/32Out OP5251 carrier, section A refers to the 32 input lines and section B to the 32 output lines,
  • the Sub-Section, 1 to 4, is a subset of 8 channels connected to one DataOut port: subset 1 represents the 8 first channels of one section of the OP525x, subset 2 represents the 8 next channels, etc.

The user must refer to the configuration file (opened with any text editor) for selecting the DataOut port number for the desired digital input channels. The OP5142EX1 Event Detector block then parses the configuration file and displays the Slot, Section and Sub-section values corresponding to the DataOut port number in the 'Slot info' parameter.

The maximum number of digital input channels controlled by one OP5142EX1 Event Detector is limited by the size of the subset of channels in one sub-section which is fixed to 8 in the current implementation.

The maximum number of transition data returned by the DataOut port is set to 250 in the current implementation. This is the total number of transitions that can be reported for the group of 8 channels connected to that DataOut port. In order to decrease data transfer times between the OP5142 and the model, the user can decrease the number of transition information returned to the model to the actual expected number of transitions per calculation step, with the use of the 'Expected number of events per channel' parameter.


Controller NameBind this block to an OpCtrl OP5142EX1 block by entering the same 'Controller Name' as specified in the OpCtrl OP5142EX1 block The OpCtrl OP5142EX1 block controls initialization of the settings of one specific OP5142 card in the system.
DataOut port numberEnter the number of the DataOut port to be controlled by this block, in the range [1:32].
Slot infoThis non-editable parameter displays the physical location of the digital input channels related to the selected DataOut port, as obtained from the parsing of the configuration file.
Maximum number of channels controlled by this blockThis non-editable parameter displays the number of channels in one sub-section listed in the configuration file, typically 8.
Number of channelsEnter the number of channels for which data values will be returned at each calculation step. This number must be less than or equal to the value of the 'Maximum number of channels' parameter. The data transfer mechanism between RT-LAB and the OP5142 does not allow the selection of individual channels in the sub-section of channels. The data returned by the block will thus correspond to the N first channels of the sub-section, where N is the value of the 'Number of channels' parameter.
Expected number of events per channelThis parameter controls the amount of transition data transferred from the OP5142 to the RT-LAB model at each calculation step. If the value entered is a single integer value, it applies to all channels. The value can also be entered as a vector of values, each element of the vector specifying the number of events for one channel. This parameter is used to set the widths of the States and Times outputs.
Time unitSelect the time unit of the Times output values. If 'Time ratio' is selected, the Times values returned to represent the ratio of the transition time relative to the beginning of the calculation step, over the duration of the step. If 'Seconds' is selected, the Time values represent the delay between the beginning of the calculation step and the time of the occurrence of the transition.
Sample Time (s)This parameter allows the user to specify the block sample time in seconds. The default value is 0, which specifies a continuous sample time (note that the sample time is borrowed from the separated subsystem) while -1 specifies an inherited sample time. A functionality block and its associated controller block must execute at the same sample time.


This block has no inputs


This block has one States and one Times output for each channel, plus one global Status output.

States and Times outputs return values in chronological order, i.e. the first value of each States and Times vectors corresponds to the first transition that occurred on the digital input channel during the previous calculation step, the second value to the second transition etc.

The outputs can take the following values:


Possible Values Description 
1Rising edge transition detected 
0Falling edge transition detected
-1No transition occurred


Possible Values (time ratio) Description 
0 <= x < 1 The ratio of the time of occurrence of the transition (Ttr) over the duration of the calculation step (Ts). Ttr is the time offset of the transition relative to the beginning of the calculation step where the transition occured: Ttr = [0:Ts]; and x = Ttr / Ts 
1No transition occurred 
Possible Values (seconds) Description 
0 <= x < Ts Time elapsed between the beginning of the calculation step and the occurrence of transition
Ts No transition occurred 


0No error.

Block could not be matched with an OpCtrl OP5142EX1 block (check the 'controller Name' value), or OP5142 card initialization problem.

-2Data reception timeout. This error can be caused by model synchronization errors,

Data reception error: the block received fewer data from the OP5142 card than the value expected according to the 'Expected number of events' parameter. Missing data were replaced by 0.


Data reception error: the block received more data from the OP5142 card than the value expected according to the 'Expected number of events' parameter. Extra data were discarded.

Characteristics and Limitations

PWM Processing

When the Event Detector block is used to capture PWM signal, processing time increases with the number of events to compute so it increases with the PWM frequency and the number of channels. The amount of data transferred between the FPGA and CPU also increases with the number of events since the transition times must be transferred for each step.

Connector Pin Assignments

The user should refer to the documentation of the OP525x carrier for connector pin assignments.

Direct FeedthroughNo
Discrete sample timeYes
XHP supportYes
Work offlineNo

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