What's New in C51 Version 9.05

• [C51 Compiler]
  • Improved: access to bit-field members with size 1 bit. The compiler uses bit instructions to access such bit-field members objects that are defined with the bdata memory type. This is now extended also to structs that are defined with the extern attribute.
  • Corrected: Common sub-expression elimination can deliver incorrect values when array pointers are used. Example:
    

    int foo (unsigned char dat[]) {
    int len1, len2, ofs;
    
      ofs = 5;
      len1 = dat[ofs];
      if(len1 > 0x10)  return -1;
      ofs += len1 + 1;             // modify 'ofs'
      len2 = dat[ofs];             // 'dat[ofs]' not reloaded, instead value of 'len1' is used
      return len2;
    }
    
    

  • Corrected: Wrong code with pointer arithmetic and conversions to long. Example:

    unsigned char *p;
    unsigned int code a1[10];
    unsigned char xdata a2[500;
    
    void foo (void) {
      unsigned long r1 = (unsigned long)(p - (a2 + a1[0]));                  // wrong
      unsigned long r2 = (unsigned long)(p - (unsigned long)(a2 + a1[0]));   // work around
    }
    
    

  • Corrected: Pointer arithmetic with conversion to 'unsigned long' rejected. Example:

    unsigned char xdata *ptr1;
    unsigned char xdata *ptr2;
    unsigned long i4;
    
    void foo (void) {
      i4 = (ptr1 - ptr2); // pointer conversion rejected, instead an error was issued
    }
    
    

• [LX51 Linker/Locater]
  • Corrected: When Linker Code Packing is used with a banking application,segments or the content of segments may get lost. This problem was introduced with C51 Version 9.03.
• [New Supported Devices]
  • CoreRiver ADCore200, ADCore210, ADCore220, AmpCore100, ChargerCore2.0, GC230, GC400, GC410, GC81L541A0, GC81L581A0, GC81L591A0, GC89L541A0, GC89L581A0, GC89L591A0, and HallCore110 davices.
  • Nordic nRF8200 device.
  • Nuvoton N78E055A, N78E059A, N78E366A, N78E517A, N79E234, N79E235, N79E342, N79E352, N79E822, N79E823, N79E824, N79E825, N79E843, N79E844, N79E845, N79E853, N79E854, N79E855, N79E875, W78E051D, W78E052D, W78E054D, W78E058D, and W78E516D devices.
  • Silabs C8051T620, C8051T621, C8051T622, C8051T623, C8051T320, C8051T321, C8051T322, C8051T323, C8051T326, C8051T327, C8051F380, C8051F381, C8051F382, C8051F383, C8051F384, C8051F385, C8051F386, and C8051F387, devices.
• [µVision4]
  This C51 release comes with µVision V4.22.00.