| Multiparameter physiological monitor can provide significant parameter evidence for clinical diagnosis in the way that monitor multiple physiological parameters at the same time. It's difficult to be extended greatly because of the high cost and large volume, even though a large need from multiple fields besides hospital appears along with the the rapidly information technology development, life science technology development, and so on.The development of embedded system combines the advanced computational techniques with the specific application closely. It is very suitable for the situation with strict requirement on cost, performance, volume and power consumption, because the high-efficiency design of its software and hardware enable a higher system performance under the same resources.It shows that the advantage of embedded system completely meets the demand of the development of portable multiparameter monitor. Therefore, we designed and realized the basic function of back part of the monitor, making use of the embedded system development technology. Based on ARMSYS2410 development board and PC, we built the platform for our development. We realized the stream-driver for AD part in Windows CE 5.0, and proposed the detailed flow of upper application program. Implementation of anolog-to-digital conversion for physiological parameter was finished perfectly. The converted data could be displayed in real time, be played back later, and could also be read and displayed on PC, which proved the validity of our saved data. Also, the analyses and the solutions to the main problems in the development are presented in the thesis.Firstly, based on the current situation of domestic monitor, we chose the cost-effectiveS3C2410 microprocessor with low price and high speed as the major chip of the system hardware, took the Windows CE 5.0 embedded operation system as the core of the system software. Rooted from Windows CE 5.0, we customed operation system which would work on the board. Through USB and serial communition between PC and the board, we sent the kernel run-time image file to the board, and it could work well.Secondly, according to the working principle of the PWM Timer and the 10-bit anolog-to-digital conversion on the S3C2410 chip, the operating mechanism of the stream-interface driver , and the interrupt handling mode under Windows CE 5.0, we realized the stream-interface driver for the AD part in the monitor, whose sample rate was controlled by the interrupt frequency of the PWM Timer. We developed the driver in Platform Builder. There were some tasks in the driver, such as, set relative registers about the hardware and some global variables, created IST to deal with PWM interrupt, and so on. In the PWM IST, we read the anolog-to-digital conversion data and started the next AD.Thirdly, we developed the upper application in the EVC to control the AD through the communication with the OS, such as, load/unload/open/close the driver, set parameter to control the output frequency of the PWM timer, get the current output frequency of timer, start or stop timer, and so on. We can display the waveform in real-time, save the conversion data in time, and play back the saved data.Then, working with 900 Hz PWM Timer interrupt frequency(up to 1660Hz so far), we conducted experiments through our driver and upper application to collect electrocardiosignal, pulse, and sine wave(or pyramidal wave) at the same time. Good waveforms could be displayed and played back perfectly after debugging hardward and softward time after time. The saved data file could be read and displayed on PC successfully. Therefore, our driver and application programme could be used in the future development for data analyse and process in the monitor.The paper ends with analyses and conclusions about what we've done so far and the existing problems, and the research direction of the future work is prospected.
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