We propose a scheme of a digitally controlled microwave frequency comb (MFC) based on a Mach–Zehnder modulator (MZM) and pulse signals. In the proposed scheme, an MZM is driven by a periodic pulse signal that is controlled with binary sequences and then outputs an optical frequency comb (OFC). After the beat frequency occurs among modes of the OFC, an MFC with a wide spectrum coverage and small power variation is obtained using a photodetector. The theoretical model of the MFC generation based on pulse signals is developed. The performance of the MFC generation scheme is investigated. The results show that the minimum power variation and maximum spectrum bandwidth of the generated MFC are 0.31 dB and 300 GHz, respectively. By programming the binary sequence, the frequency spacing of MFC and the number of microwave signals can be tuned in the range of 1.25 to 10 GHz and 31 to 255, respectively.