Development And Implementation Of Low-level Driver Software For Scalar Network Analyzer

The Scalar Network Analyzer(SNA) is one of the indispensable tools in microwave test scopes. The fast developing microwave technology asks for higher performance of microwave test tools, and foreign microwave technology and their SNAs lead this field. Domestic microwave technology research starts later than foreign countries and the technology level is not as prior as others, so that most of our microwave test instruments are low-end. On this background, we research and design this SNA, ranging from 300KHz to 1300MHz.This paper mainly concerns the underlying driving program of the SNA with LPC2220 as the main controller and CPLD as the LCD controller. The SNA uses the ARM+CPLD framework, with its control and process underlying software completed on ADS1.2 of ARM Corporation, and its LCD display and some control driving program on Quartus II of Altera Corporation.This paper introduces the SNA's underlying driving program structure, summarizes the subassembly and working theory, expatiates the underlying software in ARM, and the display and some control hardware language design in CPLD.The underlying software in ARM achieves the functions below: the key value read and processing, the frequency setting(including the swept generator, DDS, PLL and the local frequency generator), the data read and processing, the data display, the waveform display, the function module display, the test mode regulation, the display mode regulation, the reference line regulation, and the system parameter saving and recall, etc.The driving program in CPLD achieves the functions below: making the LCD display normally, the read and writing of CPLD's external SRAM, the setting of DDS, D/A, VCO, the read of channel A/Ds and key value.Up to now, the SNA has been completed with the software-hardware debugging. It works well and can display SNA's functions, read and process key values, set frequency, read and process channel data and so on.