实现了12位DA转换芯片ad767与C8051F020的接口数据采集和控制，并提供矩阵键盘控制和数码管显示。-Implementation of the DA converter 12 and C8051F020 chip AD767 interface data acquisition and control, and provides control of matrix keyboard and digital display.

实现AD767的正常工作，其中P1和P3的第四位依次是地位至高位-To achieve the normal work of AD767, in which P1 and P3, followed by the fourth position to the high