双机可调波形发生器，通过一片单片机的两路电压和按键输入，来得到输出波形的频率、幅度、种类，然后发送给另一个单片机来产生特定的波形-Dual adjustable waveform generator, via a microcontroller and two key input voltage to obtain the frequency of the output waveform, magnitude, type, and then sent to another microcontro

A bottom-up parse corresponds to the construction of a parse tree for an input string beginning at the leaves (the bottom) and working up towards the root (the top) . It is convenient to describe parsing as the process of building parse trees, althou