A Small Control System Using 8051: uart.c Source File

00001 /**************************************************
00002 * Function: Driver for 8051 uart interface  
00003 *           
00004 * File:    uart.c
00005 * Author:  Book Chen
00006 * 2008.08.08 
00007 ****************************************************
00008 */
00009 #include "..\inc\includes.h"
00010 
00011 struct UART_CONTROL UartCtrl; 
00012 bit bUartTransfer;
00013 
00014 void  F_UartPowerOnInit(void) LargeReentrant;
00015 void  F_UartSvc(void) LargeReentrant;
00016 void  F_UartKeyInPut(INT8U KeyCode) LargeReentrant;
00017 INT8U F_UartKeyInGet() LargeReentrant;
00018 INT8U F_UartCheckKeyInBuffer() LargeReentrant;
00019 void  F_UartKeyOutPut(INT8U) LargeReentrant;
00020 INT8U F_UartKeyOutGet() LargeReentrant;
00021 INT8U F_UartKeyOutGetIsr() LargeReentrant;
00022 INT8U F_UartCheckKeyOutBuffer() LargeReentrant;
00023 INT8U F_UartCheckKeyOutBufferIsr() LargeReentrant;
00024 char  putchar(char) LargeReentrant;
00025 char  getchar(void) LargeReentrant;
00026 
00027 void F_UartPowerOnInit(void) LargeReentrant{
00028     // Initial UART H/W
00029     SCON|=0x50;        // serial configuration register...
00030                        // bit76=01 mode 1 8 bit uart,bit4=1 receive enable.
00031     ES=1;              // Enable serial interrupt...interrupt 4
00032     // variable initial    
00033     bUartTransfer=0;
00034     UartCtrl.KeyInGet=0;
00035     UartCtrl.KeyInPut=0; 
00036 }
00037 void F_UartKeyInPut(INT8U KeyCode) LargeReentrant{
00038     if(UartCtrl.KeyInPut<(KEY_IN_BUFFER_SIZE-1)){
00039         if((UartCtrl.KeyInPut+1)!=UartCtrl.KeyInGet){
00040             UartCtrl.KeyInPut++;
00041             UartCtrl.KeyInBuffer[UartCtrl.KeyInPut]=KeyCode;
00042         }
00043     }
00044     else{
00045         if(UartCtrl.KeyInGet==0);
00046         else{
00047             UartCtrl.KeyInPut=0;
00048             UartCtrl.KeyInBuffer[UartCtrl.KeyInPut]=KeyCode;
00049         } 
00050     }
00051 }
00052 INT8U F_UartKeyInGet(void) LargeReentrant{
00053     if(UartCtrl.KeyInGet!=UartCtrl.KeyInPut){
00054         if(UartCtrl.KeyInGet<(KEY_IN_BUFFER_SIZE-1)){
00055             UartCtrl.KeyInGet++;
00056             return UartCtrl.KeyInBuffer[UartCtrl.KeyInGet];      
00057         }
00058         else{         
00059             UartCtrl.KeyInGet=0;
00060             return UartCtrl.KeyInBuffer[UartCtrl.KeyInGet];
00061         }
00062     }
00063     return 0xff;
00064 }
00065 INT8U F_UartCheckKeyInBuffer(void) LargeReentrant{  // check key in buffer status
00066     if(UartCtrl.KeyInPut<(KEY_IN_BUFFER_SIZE-1)){
00067         if((UartCtrl.KeyInPut+1)==UartCtrl.KeyInGet) return UART_KEY_BUFFER_FULL;       
00068         else if(UartCtrl.KeyInGet!=UartCtrl.KeyInPut) return UART_KEY_BUFFER_NOT_FULL;        
00069         else return UART_KEY_BUFFER_EMPTY;                                      
00070     }
00071     else{
00072         if(UartCtrl.KeyInGet==0) return UART_KEY_BUFFER_FULL;                        
00073         else if(UartCtrl.KeyInGet!=UartCtrl.KeyInPut) return UART_KEY_BUFFER_NOT_FULL;    
00074         else if(UartCtrl.KeyInGet==(KEY_IN_BUFFER_SIZE-1)) return UART_KEY_BUFFER_EMPTY;   
00075     }
00076 }
00077 char putchar(char c) LargeReentrant{ 
00078     while(bUartTransfer==1);                        
00079     if(c==0x0a){
00080         SBUF=0x0d;
00081         bUartTransfer=1;
00082         while(bUartTransfer==1);   
00083     }
00084     SBUF=c;
00085     bUartTransfer=1;
00086     while(bUartTransfer==1);   
00087     return c;
00088 }
00089 char getchar(void) LargeReentrant{                         
00090     while(F_UartCheckKeyInBuffer()==UART_KEY_BUFFER_EMPTY);  
00091     return (F_UartKeyInGet());
00092 }
00093 
00094 
00095 
00096