The Foxtrot CP-2061 is equipped with dynamic NFC memory, which enables bidirectional data exchange between a mobile device and a PLC. Communication is carried out via an internal serial channel in MEM mode (TXV00469). A data area is available that can be read from and written to the PLC wirelessly using a mobile device with NFC.
Mobile App for Reading and Writing Data
To work with NFC memory, you need to develop your own mobile app or use existing, readily available tools. One example is the ST NFC Tap app, which is available for Android and iOS. The app allows you to easily read the current contents of the NFC memory into your phone or, alternatively, save prepared data from your phone to the device’s memory.
Recommended data structure
The user must design and adhere to their own data structure, which will be interpreted in both the mobile app and the PLC program. To ensure reliable data transfer, it is recommended to use a simple header + payload + checksum byte structure. For example:
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Header – information identifying the format or version and the length of the following data.
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Payload – the data itself (device parameters, configuration values, etc.).
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Checksum byte – a simple checksum or CRC to verify the integrity of the transmitted data.
Data organized in this way can be easily recognized by the PLC, allowing it to detect any errors before processing them.
Use cases
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Offline Configuration: Device commissioning can be simplified by reading or writing a custom configuration set. During installation, the user can, for example, read the PLC’s IP address, the DHCP address assigned by the server, etc.
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Service transfers: During maintenance, operational data or error logs can be quickly read from memory to a mobile phone. NFC allows important data to be transferred to and from the device without the need for a physical connection.
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Simple parameter entry: For minor parameter changes (e.g., setting time intervals, temperature limits, etc.), the user can use a phone with a pre-prepared profile. When the phone is placed against the device, the new value is saved to the NFC memory, and the PLC reads it as a standard data input.
In this way, the NFC memory in the Foxtrot CP-2061 expands the possibilities for fast and direct communication with the device without the need for complicated program changes or connecting additional hardware.