ftp://mcu123:mcu123@mcu123.com/%D2%D1%D5%FB%C0%ED%C4%BF%C2%BC/%BF%AA%B7%A2%B9%A4%BE%DF%C8%ED%BC%FE/51/c51v906_mcu123.rar
这个下载比较快。

What's New in C51 Version 9.06

    [New Supported Devices]
        Atmel AT89LP51RB2, AT89LP51RC2, AT89LP51IC2, AT89LP51RD2, AT89LP51ED2, and AT89LP51ID2 devices.
        Infineon TLE9831, TLE9832, TLE9833, TLE9834, and TLE9835 devices.
        Maxim 71M6531D, 71M6531F, 71M6532D, 71M6532F, 71M6534H, 71M6541D, 71M6541F, 71M6542F, 71M6543F, and 71M6543G devices.
        Silabs C8051F969, C8051F968, C8051F967, C8051F966, C8051F965, C8051F964, C8051F963, C8051F962, C8051F961, C8051F960, Si1037, Si1036, Si1035, Si1034, Si1033, Si1032, Si1031, Si1030, Si1027, Si1026, Si1025, Si1024, Si1023, Si1022, Si1021, and Si1020 devices.
    [Device Support]
        Added: Quick_Test example for Infineon TLE983x based devices in folder ..C51ExamplesInfineon TLE983x.
        Added: banking example for Maxim 71M6543G device in folder ..C51ExamplesMaximBankEx1.
        Added: banking example for Maxim 71M6534H device in folder ..C51ExamplesMaximBankEx2.
    [µVision4]
        This C51 release comes with µVision V4.24.00.