Abstract
This paper describes an indicator system that helps prevent errors by pharmacists when filling a prescription. It uses an optical tag scanner to read a barcode or QR-code tag that encodes the prescribed medicine and lights up the corresponding cell in the medicine cabinet. The scanning subsystem used by the pharmacist is connected to the database wirelessly via Bluetooth Low Energy Technology (BLE) for easy deployment. The indicator subsystem uses a novel row-column scanning circuitry to minimize the number of general-purpose input/output (GPIO) pins that are required of the microcontroller unit (MCU) for maximum scalability and minimum hardware. Experimental results in a real pharmacy setting show the proposed system to be effective in minimizing dispensing errors while meeting cost and performance targets for commercial use.