Abstract: A dispenser interface module connects with an existing main processing board of a fuel dispenser via an existing data port of the main board and via a current loop communication link connection of the main board. The dispenser interface module determines an idle condition of the dispenser from analysis of signals on the link, without disturbing the signals on the link, and only performs actions such as reboot or software update of the main board, or retrieval of data from the main board through the data port, during the idle condition. The dispenser interface module may compress data retrieved through the data port by removing previously retrieved records from the retrieved data. The dispenser interface module instructs a communication module to wirelessly transmit the compressed data to a remote server for analysis. The communication module wirelessly receives, and forwards to the dispenser interface module, reboot or update messages and instructions.