pc_o.lst

Embedded C 这本书的范例光碟程式

C51 COMPILER V6.21  PC_O                                                                   01/23/2002 18:10:46 PAGE 1   


C51 COMPILER V6.21, COMPILATION OF MODULE PC_O
OBJECT MODULE PLACED IN PC_O.OBJ
COMPILER INVOKED BY: C:\KEIL\C51\BIN\C51.EXE PC_O.c OPTIMIZE(6,SPEED) BROWSE DEBUG OBJECTEXTEND

stmt level    source

   1          /*------------------------------------------------------------------*-
   2          
   3             PC_O.C (v1.00)
   4          
   5            ------------------------------------------------------------------
   6          
   7             Core files for simple write-only PC link library for 8051 family
   8             [Sends data to PC - cannot receive data from PC]
   9          
  10             Uses the UART, and Pin 3.1 (Tx) 
  11          
  12             See text for details (Chapter 9).
  13          
  14             COPYRIGHT
  15             ---------
  16          
  17             This code is associated with the book:
  18          
  19             EMBEDDED C by Michael J. Pont 
  20             [Pearson Education, 2002: ISBN: 0-201-79523-X].
  21          
  22             This code is copyright (c) 2001 by Michael J. Pont.
  23           
  24             See book for copyright details and other information.
  25          
  26          -*------------------------------------------------------------------*/
  27          
  28          #include "Main.h"
  29          #include "PC_O.h"
  30          
  31          // ------ Public variable definitions ------------------------------
  32          
  33          tByte Out_written_index_G;  // Data in buffer that has been written 
  34          tByte Out_waiting_index_G;  // Data in buffer not yet written
  35          
  36          // ------ Private function prototypes ------------------------------
  37          
  38          static void PC_LINK_O_Send_Char(const char);
  39          
  40          // ------ Private constants ----------------------------------------
  41          
  42          // The transmit buffer length
  43          #define TRAN_BUFFER_LENGTH 20
  44          
  45          // ------ Private variables ----------------------------------------
  46          
  47          static tByte Tran_buffer[TRAN_BUFFER_LENGTH];
  48          
  49          static tByte Time_count_G = 0;
  50          
  51          
  52          /*------------------------------------------------------------------*-
  53          
  54            PC_LINK_O_Update()
  55          
C51 COMPILER V6.21  PC_O                                                                   01/23/2002 18:10:46 PAGE 2   

  56            Sends next character from the software transmit buffer
  57          
  58            NOTE: Output-only library (Cannot receive chars)
  59          
  60            Uses on-chip UART hardware.
  61          
  62          -*------------------------------------------------------------------*/
  63          void PC_LINK_O_Update(void)
  64             {
  65   1         // Deal with transmit bytes here
  66   1         //
  67   1         // Are there any data ready to send?
  68   1         if (Out_written_index_G < Out_waiting_index_G)
  69   1            {
  70   2            PC_LINK_O_Send_Char(Tran_buffer[Out_written_index_G]);     
  71   2      
  72   2            Out_written_index_G++;
  73   2            }
  74   1         else
  75   1            {
  76   2            // No data to send - just reset the buffer index
  77   2            Out_waiting_index_G = 0;
  78   2            Out_written_index_G = 0;
  79   2            }
  80   1         }
  81          
  82          /*------------------------------------------------------------------*-
  83          
  84            PC_LINK_O_Write_String_To_Buffer()
  85          
  86            Copies a (null terminated) string to the character buffer.  
  87            (The contents of the buffer are then passed over the serial link)
  88          
  89          -*------------------------------------------------------------------*/
  90          void PC_LINK_O_Write_String_To_Buffer(const char* const STR_PTR)
  91             {
  92   1         tByte i = 0;
  93   1      
  94   1         while (STR_PTR[i] != '\0')
  95   1            {
  96   2            PC_LINK_O_Write_Char_To_Buffer(STR_PTR[i]);
  97   2            i++;
  98   2            }
  99   1         }
 100          
 101          /*------------------------------------------------------------------*-
 102          
 103            PC_LINK_O_Write_Char_To_Buffer()
 104          
 105            Stores a character in the 'write' buffer, ready for 
 106            later transmission
 107           
 108          -*------------------------------------------------------------------*/
 109          void PC_LINK_O_Write_Char_To_Buffer(const char CHARACTER)
 110             {
 111   1         // Write to the buffer *only* if there is space
 112   1         // (No error reporting in this simple library...)
 113   1         if (Out_waiting_index_G < TRAN_BUFFER_LENGTH)
 114   1            {
 115   2            Tran_buffer[Out_waiting_index_G] = CHARACTER;
 116   2            Out_waiting_index_G++;     
 117   2            }
C51 COMPILER V6.21  PC_O                                                                   01/23/2002 18:10:46 PAGE 3   

 118   1         }
 119          
 120          /*------------------------------------------------------------------*-
 121          
 122            PC_LINK_O_Send_Char()
 123          
 124            Based on Keil sample code, with added (loop) timeouts.
 125            Implements Xon / Off control.
 126          
 127            Uses on-chip UART hardware.
 128          
 129          -*------------------------------------------------------------------*/
 130          void PC_LINK_O_Send_Char(const char CHARACTER)
 131             {
 132   1         tLong Timeout1 = 0;
 133   1      
 134   1         if (CHARACTER == '\n')  
 135   1            {
 136   2            Timeout1 = 0;
 137   2            while ((++Timeout1) && (TI == 0));  
 138   2      
 139   2            if (Timeout1 == 0)
 140   2               {
 141   3               // UART did not respond - error
 142   3               // No error reporting in this simple library...
 143   3               return;
 144   3               } 
 145   2      
 146   2            TI = 0;
 147   2            SBUF = 0x0D;  // Output CR  
 148   2            }
 149   1        
 150   1         Timeout1 = 0;
 151   1         while ((++Timeout1) && (TI == 0));  
 152   1      
 153   1         if (Timeout1 == 0)
 154   1            {
 155   2            // UART did not respond - error
 156   2            // No error reporting in this simple library...
 157   2            return;
 158   2            } 
 159   1      
 160   1         TI = 0;
 161   1      
 162   1         SBUF = CHARACTER;
 163   1         }
 164          
 165          /*------------------------------------------------------------------*-
 166            ---- END OF FILE -------------------------------------------------
 167          -*------------------------------------------------------------------*/


MODULE INFORMATION:   STATIC OVERLAYABLE
   CODE SIZE        =    189    ----
   CONSTANT SIZE    =   ----    ----
   XDATA SIZE       =   ----    ----
   PDATA SIZE       =   ----    ----
   DATA SIZE        =     23       9
   IDATA SIZE       =   ----    ----
   BIT SIZE         =   ----    ----
END OF MODULE INFORMATION.


C51 COMPILATION COMPLETE.  0 WARNING(S),  0 ERROR(S)