Lector8xx / CLV8xx Command Protocol

The document attached to this knowledge article provides a comprehensive technical reference for the Lector8xx / CLV8xx Command Protocol, the command interface used to access configuration parameters, status information, diagnostic data, and executable actions of the reader. The protocol enables integration with PLCs, host computers, engineering tools, service applications, and custom software through a simple and human-readable command interface. The Text Command Protocol is available through multiple communication channels, including:

• Ethernet TCP/IP
• Serial (data)
• Serial (service)
• Fieldbus

All protocol messages use mandatory framing characters to ensure reliable command parsing and transmission. Every command sent to the device and every response returned by the device must be enclosed between a Start of Text (<STX>, Hex ASCII 0x02) character and an End of Text (<ETX>, Hex ASCII 0x03) character. The device will only process commands that are correctly framed with <STX> and <ETX>.

The protocol supports three fundamental command types:

Read commands retrieve the current value of a device parameter.

Example: <STX>read DeviceName<ETX> Response: <STX>read DeviceName "Lector85x"<ETX>

Write commands modify the value of a writable parameter.

Example: <STX>write DeviceName "Reader01"<ETX> Response: <STX>written DeviceName<ETX>

Run commands execute device methods or actions.

Example: <STX>run ApplyParameterChanges<ETX> Response: <STX>run ApplyParameterChanges<ETX>

The protocol distinguishes between parameter modification and parameter activation. When parameters are written, the new values are first stored in the device configuration but are not yet active. Multiple parameters can therefore be modified consecutively without immediately affecting the running application. To make pending configuration changes effective, the following action must be executed:

<STX>run ApplyParameterChanges<ETX>

Only after successful execution of ApplyParameterChanges all pending parameter changes are transferred into the active device configuration and used by the running application. This mechanism allows several related parameters to be changed together and activated simultaneously, preventing inconsistent intermediate configurations.