矩阵键盘+数码管显示‘0~F’
..........................\4.4.c
..........................\4.4.LST
..........................\4.4.OBJ
..........................\4。4
..........................\4。4.hex
..........................\4。4.lnp
..........................\4。4.M51
..........................\4。4.plg
..........................\4。4.uv2
..........................\STARTUP.A51
..........................\STARTUP.LST
..........................\STARTUP.OBJ