利用AVR单片机设计IIR 低通滤波器，其中截止频率、抽样频率都有说明，运行环境是先用IICAVR建立工程，再将该代码加入进去即可-Use AVR microcontroller IIR low-pass filter, which cut-off frequency, sampling frequency with specifications, running environment is to use IICAVR build project, then the code can join

Arduino库。在AVR芯片上实现fir和iir滤波，也可以用在其它平台上-Arduino library. Achieve fir and iir filter on AVR chip can also be used on other platforms