时钟模块（完成）
................\STARTUP.A51
................\STARTUP.LST
................\STARTUP.OBJ
................\时钟
................\时钟.LST
................\时钟.M51
................\时钟.OBJ
................\时钟.c
................\时钟.hex
................\时钟.lnp
................\时钟.plg
................\时钟.uvopt
................\时钟.uvproj
................\时钟_uvopt.bak
................\时钟_uvproj.bak