What's New in C51 Version 9.51

• [New Supported Devices]
  • Silicon Laboratories Inc.
    C8051F370, C8051F371, C8051F374, C8051F375, C8051F390, C8051F391, C8051F392, C8051F393, C8051F394, C8051F395, C8051F396,
    C8051F397, C8051F398, C8051F399, C8051T620, C8051T621, C8051T622, C8051T623, C8051T626, and C8051T627.
• [C51 Compiler]
  • Corrected: calculation of negative constants within nested calls may create incorrect results (this problem was introduced in C51 V9.50a). For example:

    #define TDO  5
    #define GET_TDO()   (Arr[TDO])
    
    unsigned char xdata Arr[10];
    
    unsigned char TestTDO() {
      unsigned char ret;
      ret = (unsigned char)(((GET_TDO()-1)*2)-1);   // Incorrect result. For the negative constant a subtraction has been used instead of an addition.
      return ret;
    }
    

  • Corrected: incorrect pointer arithmetic with subtract of unsigned int variables for XDATA arrays with sizeof < 256 bytes. For example:

    unsigned char xdata b[256];  /* Problem does not exist when array size > 256  */
    void xdata *p;
    unsigned int i = 256;        /* Problem only appears for unsigned int variables */
    
    void main (void)  {
      p = &b[256-i];             /* Works no problem when array index is used */
      p = b + 256 - i;           /* Failed on pointer arithmetic when uint variable is subtracted */
    }
    
    

• [LX51 Linker/Locater]
  • Corrected: a potential DPTR corruption which may occurs in code-banking applications when Global Register Coloring is enabled.
• [µVision4]
  • This C51 release comes with µVision V4.60.6.8.
  • Enhanced: the Logic Analyzer allows rearranging signals through a simple drag&drop of the signal name. Signals can be scaled in width and height.
  • Corrected: under certain circumstances the Source Browser incorrectly reported several definitions of an "enum".
  • Refer to Revision History for a complete list.