HENGSTLER RS53 sinecosine encoder was selected,in combination with 13bit sine wave signal interpolation subdivision chip iCNQI and the HEIDENHAIN ND281B digital readouts,a high precision AC servo drive and control experimental platform was built.The initialization registers of iCNQI chip were configured by using serial BISS communication protocol,which was accomplished by FPGA and VHDL. The current speed,absolute angle and position value of sinecosine encoder could be digital read realtime.Experimental results show that iCNQI devices can run smoothly with reliable performance,its positioning accuracy can reach 〖BF〗0005°（18"）〖BFQ〗,repositioning accuracy can reach 〖BF〗0001°（36"）〖BFQ〗,the requirements of high resolution,high dynamic performance of servo motor control are met.It has important practical application values in industries with high accuracy,high speed CNC machining systems. 