摘要： Based on the STM32 single-chip microcomputer (SCM), the relationship between music rhythm and the output color of red-green-blue-light-emitting-diode (RGB-LED) lamp is studied in this paper. Aiming at the problem that music rhythms and colors of light cannot be fully matched, the idea that the colors of RGB-LED lamp are controlled by music rhythms is put forward. Sound collector, microcontroller, power module, bias circuit, and RGB-LED lamp are adopted in the hardware design. In the software, the music data collected by an analog-to-digital converter (ADC) is converted into digital quantities. The color of RGB tricolor is controlled by changing the ratio of pulse width modulation (PWM). With a linear function, we adjust the lighting effect when the rhythm falls and filter out some smaller values, but the improvement is not satisfactory. Therefore, the nonlinear quadratic function instead of the linear function is used to eliminate the flicker when the music rhythm becomes weak. The experimental results show that the proposed improvement can give rise to a much better control effect for the colors of light by the music rhythms.