The Marshall Pro (Fuel) protocol is a high-performance, command-based interface designed for fuel retail environments. It allows your Point-of-Sale (POS) or Forecourt Controller (FCC) to manage the full lifecycle of a transaction—from card detection to final settlement.Unlike cloud APIs, the Marshall Pro (Fuel) protocol runs locally on your station’s network. The VPOS terminal acts as a persistent TCP/IP server waiting for your application to connect.The API is categorized into four functional areas to help you build a complete customer journey:
Payment Processing
Supports single-phase (pay) and two-phase (authorize + settle) fuel transactions.
Card Detection
Read card data without an immediate charge—perfect for Loyalty and Customer ID.
User Interface
Take control of the terminal screen to show custom menus, fuel types, or prompts.
Peripheral Support
Directly trigger the integrated thermal printer for customer receipts.
Socket Management: The VPOS server maintains a single active session. If your application opens a new socket, the server automatically terminates the previous connection to ensure data integrity.
