【摘要】 介绍了用于石英晶振真空计的数据采集、气压频率非线性曲线拟合、低气压下温度补偿等诸多的软件设计 .由单片机采集的经 V/ F转换后的输出信号 fp 与石英晶振的谐振频率 fc,由软件实现采集和滤波 ,采用定时中断和外部脉冲计数中断相结合的方法来提高采集的准确性 .通过大量实验结果得出的气压 Pi 和 fp 的关系曲线分4段做非线性曲线拟合 ,当真空度小于 10 Pa时启用事先在微处理器存入的表格进行温度补偿以拓宽测量下限 .经测试 ,在 10 - 5～ 10 - 1 Pa内 ,本真空计的测量精度达 10 %～ 15 % .更多还原

【Abstract】 Many software designs used in the quartz oscillator vacuum gauge, including data sampling? nonlinear curve fitting of air pressure and frequency?temperature\|compensation in low air pressure introduced are introduced in this paper. V/F transition signal \%f\%\-p sampled by singlechip and syntonic frequency \%f\%\-c of the quartz oscillator were obtained and filtered by software. The method of combining time interruption with count interruption of interior pulse was adapted to improve the accuracy. The curve of \%P\-i\% vs \%f\%\-p obtained by a lot of experiments was divided into four segments for nonlinear curve fitting. When the vacuum value was smaller than 10 Pa, the software would do the temperature\|compensating according to the form saved in the microprocessor to widen the lower measurable limit. The experimental results showed that the vacuum gauge had 10%～15% measurement error in the 10\+\{-5\}～10\+\{-1\} Pa range.更多还原