An embedded system consists of heterogeneous layers including hardware, HAL (Hardware Abstraction Layer), OS kernel and application layer. Interactions between these layers are the software interfaces to be tested in an embedded system. The identified interfaces are important criterion that selects test cases and monitors the test results in order to detect faults and trace their causes. In this paper, we propose an automated scheme of embedded software interface test based on the emulated target board. The automated scheme enables to identify the location of interface in the source code to be tested, to generate test cases, and to determine 'pass' or fail' on the interface. We implemented the test tool called 'Justitia ' based on the proposed scheme. As a case study, we applied the 'Justitia' to mobile embedded software on the S3C2440 microprocessor and Linux kernel v2.4.20.