系统软件子程序较多，主要有延时子函数、数据刷新子函数、LCD测忙子函数

There are many system software subroutines, mainly including delay subfunction, data refresh subfunction, LCD test busy subfunction, LCD write command subfunction, LCD write data subfunction, LCD read status subfunction, LCD read data subfunction, initialization Subfunction, key scan subfunction, interrupt subfunction, etc. The more important ones are the key scan sub-function and interrupt sub-function. Now only the key scan sub-function and interrupt sub-function are introduced

There are many system software subroutines, mainly delay subfunctions, data refresh subfunctions, LCD busy subfunctions, LCD write command subfunctions, LCD write data subfunctions, LCD read state subfunctions, LCD read data subfunctions, initialization subfunctions, key scanners, interrupt subfunctions, etc. One of the most important are the key-scanning subfunctions and interrupt subfunctions. Only key-scan subfunctions and interrupt subfunctions are described

There are many subroutines in the system software, including delay subfunction, data refresh subfunction, LCD busy test subfunction, LCD write command subfunction, LCD write data subfunction, LCD read status subfunction, LCD read data subfunction, initialization subfunction, key scan subfunction, interrupt subfunction, etc. Among them, the key scan function and interrupt function are more important. Now only the key scan subfunction and interrupt subfunction are introduced<br>