自己编的超声波测距程序，单文件，编译器用的是SDCC，SDCC这方面的资料确实不多，供大家参考，里面的注释很详细，几乎每个命令都有注释，再说一遍，里面注释很详细-Ultrasonic ranging program, their own series of single file, the compiler is SDCC SDCC, this information is really not much, for your reference, which is very detailed notes, almost every command has a comment, again, inside very detailed notes!!!!!!