| With the rising demand for gas detection, gas senor arrays and their discrimination technology have already drawn a lot of attention in recent years. The research on gas senor arrays consists of three parts, which are, gas senor arrays, data acquisition board and signal processing system. However, the conventional data acquisition board has some defects, so that it can not perfectly meet the testing demand for gas senor arrays any longer.Based on this research background, in this thesis we focusd on the design of a new data acquisition board for gas senor arrays. With the processor based on ARM core and the utilization of both USB interface technology and touch panel technology, the board is able to achieve the data acquisition in the following two ways. One is to achieve data acquisition onto PC via of USB, and the other is away from PC by means of touch panel.The design of data acquisition board mainly includes two parts, i.e., hardware and software. The hardware part consists of four major parts, i.e., signal regulating circuit design of sensor arrays, ARM system module circuit design, touch panel module design and USB data transmission interface design. The software part consists of following parts as the design of porting RTOSμC/OS-II to processor based on ARM core, USB firmware program design, LCD module program design, touch panel program design, channel choosing program design, variable amplifying program design, A/D transformation program design, USB driving design and PC application program design.We discussed every soft and hardware module of the acquisition board as well as the specific design scheme. Finally, we made some corresponding tests to the board, and got some results and analyzed the data. It proved that the board can achieve the data acquisition in two ways to meet the demand of detecting gas concentrations by gas senor arrays. |
