Multi-mode universal asynchronous/synchronous receiver/transmitter (MMUART) performs serial-to-parallel conversion on data originating from modems or other serial devices, and performs parallel-to-serial conversion on data from the MSS Core Complex processor or fabric master to these devices. PolarFire SoC FPGAs contain five identical MMUART peripherals in the microprocessor subsystem (MMUART_0, MMUART_1, MMUART_2, MMUART_3, and MMUART_4).