New ((hot)) - Gilbarco Dispenser Twowire Protocol For Third Party Pump Controllers

: Numerous companies have created dedicated integration units. For instance, the Gasboy CFN Series Gilbarco Interface Unit allows a Gasboy Site Controller II to control up to 8 dual or 16 single-sided Gilbarco dispensers. Similarly, the OPW Direct Pump Control (DPC) interface, while focused on Gasboy, demonstrates the industry-wide push to reduce wiring complexity using two-wire serial communication, significantly reducing equipment costs. The equipment cost for controlling four double-sided dispensers can drop from around $4,000 with a PCM to about $1,800 with a DPC solution.

Loop current is interrupted (0mA).

. It is characterized by its efficiency, using a minimal number of characters to speed up communication across a single pair of wires. www.mchip.net Technical Specifications It is characterized by its efficiency, using a

The LRC is calculated by performing an Exclusive OR (XOR) operation on all bytes following the SOH up to and including the ETX. Core State Machine and Polling Cycle

One alternative is the interface, a faster and more robust differential serial standard often used for CRIND devices. It supports longer cable runs and is less susceptible to electrical noise. : Contains the master intent (e.g.

The PAM 5000 (PA03820000) is a modern forecourt controller designed specifically for third-party POS integration. It acts as a smart intermediary, communicating with the POS over a standard serial or IP link and handling all low-level Two-Wire dispenser control. The PAM 5000 eliminates the need for a traditional D-Box for standard pump control. Its DSB492 Current Loop module can connect directly to the Two-Wire cables, reducing hardware costs and points of failure.

⚠️ Using RS-232 or RS-485 transceivers directly – will damage the dispenser’s interface. You need a current-loop converter (e.g., B&B Electronics 232CL, or build with 4N35 optos). You need a current-loop converter (e.g.

The dispenser is actively pumping fuel and pulsing real-time volume/money data.

Every command and response envelope contains specific control characters to guarantee data integrity: Description Start of Header (0x01) ADDR Dispenser Fueling Position Address CMD / RESP Command Code or Response Type DATA Optional Payload (Volume, Amount, Status) ETX End of Text (0x03) LRC Longitudinal Redundancy Check (Checksum)

The site controller or third-party pump controller typically acts as the Active device (supplying the loop current source), while the fuel dispenser behaves as the Passive node (modulating the current loop via optocouplers).

: Contains the master intent (e.g., authorize, suspend, request totals).