说明：  AVR 168芯片硬件手册，介绍AVR硬件参数的文章，大家可以看看，包括各种寄存器，定时器，串口，等的用法，参数。
(允许输入拉丁字符的拼音 AVR 168 chip hardware manual to introduce the articles of the AVR hardware parameters, we can see, including the use of a variety of registers, timers, serial ports, etc., parameters.)