EthercatDevice.pdoRead()

[Ethercat Device]

Description

Read the input process data of a certain size which starting from the specified offset for such EtherCAT slave device.

Syntax

int pdoRead(uint32_t offset, void *data, uint32_t size);

Parameters

• [in] uint32_t offset
  The offset value of input process data for such EtherCAT slave device.
• [out] void *data
  The data buffer for reading input process data.
• [in] uint32_t size
  The size of the data buffer for reading input process data.

Return Value

Return an error code. If the returned value is zero, it indicates a successful execution of this function.

Comment

This function must be called after a successful execution of EthercatMaster::start(). This function is non-blocking and can be called within the Cyclic Callback.

Example

#include "Ethercat.h"

EthercatMaster master;
EthercatDevice_Generic slave;

uint8_t buffer[4];

void setup() {
  Serial.begin(115200);
  
  master.begin();
  slave.attach(0, master);
  master.start(1000000);
}

void loop() {
  slave.pdoRead(0, buffer, 4);
  Serial.print("Buffer: ");
  Serial.print(buffer[0]);
  Serial.print(buffer[1]);
  Serial.print(buffer[2]);
  Serial.println(buffer[3]);
  delay(1000);
}

Please see the EtherCAT Library User Manual for more QEC EtherCAT instructions and API usage.