实验板有4个按键，4个LED灯。当按下K1时，流水灯以1秒的速率流动，按下K2时，以5秒的速率流动，按下K3时从向至下流动，按下K4时，从下至上流动。当重复按下按键时，保持功能不变。 -The experimental board has four buttons, four LED lights. Flow from the bottom, press K1, light water flow rate of 1 second, press K2, the rate of flow of

大屏幕相框MP3播放器全套资料，包含原理图，实物图，c语言源程序，工程文件。-The MP3 player is controlled with command buttons displayed at left side of the screen. It start to playback when a PLAY command is generated by `Play button (somewhere on the screen in power-down state) or car