TMR0结果异常

嗨，所有的，我正在实验TMR0，给一个可变频率输出。在我的代码中，主例程读取一个电位计作为一个模拟输入的5V，并输出值到一个LCD显示器。我还有一个TMR0 ISR，它切换一个输出引脚（XOWF），以给出一个频率输出，然后加载TMR0与这是一个很好的例子，除了频率是对数的，而不是与罐的运动成线性关系。我已经记录了结果并绘制了一个Excel表和图，它是对数的。加载各种“固定”的数字到TMR0证实了同样的结果。当然有逻辑的理由，但我还没明白。有什么想法吗？特里沃



      以下为原文

    Hi All,
I'm experimenting with TMR0, to give a variable frequency output.
In my code, the main routine reads a potentiometer 0-5V as analogue input, and outputs the value to an LCD display.
I also have a TMR0 ISR which toggles an output pin (XORWF) to give a frequency output and then loads TMR0 with the complimentary of the pot value.
This all works great, except that the frequency appears to be logarithmic, not linear with the movement of the pot.
I've recorded the results and plotted an Excel table and graph, which is logarithmic.
Loading various "fixed" numbers to TMR0 confirms the same results.

I'm sure there's a logical reason, but it hasn't dawned on me yet.
Any ideas ?
Trevor