We have developed a multi-sensor system by using own multi-sensor platform LSI for versatile applications including next generation robots. For a unified system implementation, the LSI provides the followings: several principle sensor readout circuits, 8-single or 4-differential multi-channels for multi-axis sensing, outputs as a haptic driver controller, flexible system parameter configuration, a RS485 compatible differential signal serial bus communication method, and event-driven response. The LSI can realize wide variety of sensing principle sensor fusion and many sensor installation. So far, we developed 2.5mmX2.5mm size MEMS (Micro Electro Mechanical Systems)-LSI integrated 3-axis force and temperature sensing devices and a 100 device connected tactile sensor network system. However, the system was complex and it took a long time for the development. For reducing the development time and increasing system reliability, we developed an application programming interface (API) for the system. The API consists of documents and basic sensor instruction sets such as system start/stop, sensor configuration setup, capacitive type sensing, analog type sensing, temperature sensing, and digital output. By using this API, we could make high performance multi-sensor systems easily without considering detailed system structures which include sensor platform LSI based sensor nodes, FPGA based relay nodes, and a host software.