Virtual SoC platforms can shorten development time of embedded systems by enabling to develop embedded software before FPGA prototypes or SoCs are given. However, virtual platforms have a limitation in the development of sensor applications because they cannot emulate external hardware modules. Thus in this paper, we propose a virtual SoC platform that supports serial interfaces where actual sensors can be used for emulating applications. The proposed platform is implemented by integrating USBtoSerial modules with QEMU. We verify the functional correctness by comparing the results of a sensor application on the proposed virtual platform, FPGA prototype, and actual SoC.