With the rapid increase of embedded computer system applications, the reliability of embedded software has drawn particular attention from researchers and industries. Many methods for testing and verifying reliability of embedded software have been discussed. However, the existing methods are weak in test suite automatic generation and therefore difficult in tackling large numbers of embedded computer applications. In this paper, the method and the technique of generating abstract test suite and their adaptation to a computer platform are presented. An algorithm for translating a LTS (labeled transition system) into BT (behavior tree) is proposed. Consequently, the TTCN (test and testing control notation) abstract test suite that employs BT as logical structure can automatically be generated with respect to the LTS description of embedded software. A TTCN tool set based on the translation algorithm for testing embedded software is introduced, and case study of testing embedded system of Internet of things device is presented.