Quantum computers use classical embedded processors to sequence control pulses. On STM32-class microcontrollers, firmware emits operation classes (gates (X, Y, Z), measurements (MEAS), and timing barriers (WAIT)) at precise intervals. If execution time depends on a secret value, an attacker with a logic analyzer can recover that secret. This classical control plane is a largely overlooked attack surface. This work presents a simulation-based investigation of timing side-channel leakage in quantum-control firmware sequencers.