This video demonstrates software-based quadrature decoding using GPIO interrupts: Red jumpers connect PB0 to PA12 and PB8 to PB13 to trigger edge-sensitive ISRs for direction/count analysis. It contrasts with MSPM0G3507's hardware QEI module  using PB6 and PB7, where the jumpers route signals for latency or resource efficiency comparison, highlighting hardware advantages like noise filtering and 4x resolution.