安装ppb的步骤，这是一个PDA下的类似PB的开发语言，代码几乎不需要改变，就可以把PB的代码写在PDA下，神奇吧-Ppb installation steps, this is a PDA similar to PB under development language, the code is almost no need to change, you can write code to PB in the PDA, the magic it