flash_f020.c

C8051系列关于flash编程C原代码

//-----------------------------------------------------------------------------
// FLASH_F020.c
//-----------------------------------------------------------------------------
// Copyright 2002 Cygnal Integrated Products, Inc.
//
// AUTH: BW / FB
// DATE: 3 JUNE 02
//
// This program shows an example of how to read, erase, and write FLASH
// memory on an 'F02x device from application code.
//
// Target: C8051F02x
// Tool chain: KEIL C51 6.03 / KEIL EVAL C51
//

//-----------------------------------------------------------------------------
// Includes
//-----------------------------------------------------------------------------

#include <C8051F020.h>                 // SFR declarations

//-----------------------------------------------------------------------------
// 16-bit SFR Definitions for 'F02x
//-----------------------------------------------------------------------------

sfr16 DP       = 0x82;                 // data pointer
sfr16 TMR3RL   = 0x92;                 // Timer3 reload value
sfr16 TMR3     = 0x94;                 // Timer3 counter
sfr16 ADC0     = 0xbe;                 // ADC0 data
sfr16 ADC0GT   = 0xc4;                 // ADC0 greater than window
sfr16 ADC0LT   = 0xc6;                 // ADC0 less than window
sfr16 RCAP2    = 0xca;                 // Timer2 capture/reload
sfr16 T2       = 0xcc;                 // Timer2
sfr16 RCAP4    = 0xe4;                 // Timer4 capture/reload
sfr16 T4       = 0xf4;                 // Timer4
sfr16 DAC0     = 0xd2;                 // DAC0 data
sfr16 DAC1     = 0xd5;                 // DAC1 data

//-----------------------------------------------------------------------------
// MAIN Routine
//-----------------------------------------------------------------------------

void main (void) {
   unsigned char xdata * idata pwrite; // pointer to FLASH used for writes
                                       // NOTE: this pointer must be located
                                       // in <data> or <idata> space!

   unsigned char code *pread;          // pointer to FLASH used for reads
   
   char EA_save;                       // saves the current state of the 
                                       // interrupt enable bit.

   // test string stored in FLASH
   unsigned char code test_string[] = "Howdy!";
   
   // disable watchdog timer
   WDTCN = 0xde;                       
   WDTCN = 0xad;

   // PART A -- erase the FLASH page at 0x1000
   
   // initialize write/erase pointer
   pwrite = (unsigned char xdata *) 0x1000;   

   EA_save = EA;                       // save interrupt status   
   EA = 0;                             // disable interrupts (precautionary)
   
   FLSCL |= 0x01;                      // enable FLASH writes/erases from
                                       // user software
   
   PSCTL = 0x03;                       // MOVX writes erase FLASH page

   *pwrite = 0;                        // initiate page erase

   PSCTL = 0;                          // MOVX writes target XRAM
   
   FLSCL &= ~0x01;                     // disable FLASH writes/erases from
                                       // user software  
   
   EA = EA_save;                       // re-enable interrupts
   
   // PART B -- copy test string to FLASH memory at address 0x1000
   
   // initialize FLASH read pointer
   pread = (unsigned char code *) test_string;

   EA_save = EA;                       // save interrupt status
   EA = 0;                             // disable interrupts (precautionary)
   pwrite = 0x1000;                    // initialize FLASH write pointer
   
   FLSCL |= 0x01;                      // enable FLASH writes/erases from
                                       // user software
      
   PSCTL = 0x01;                       // MOVX writes target FLASH memory

   while (*pread != '\0') {            // copy until NULL is detected

      *pwrite = *pread;                // copy byte

      pread++;                         // advance pointers
      pwrite++;
   }

   *pwrite = '\0';                     // NULL-terminate string

   PSCTL = 0x00;                       // MOVX writes target XRAM
   
   FLSCL &= ~0x01;                     // disable FLASH writes/erases from
                                       // user software   

   EA = EA_save;                       // re-enable interrupts
   
// PART C -- erase the scratchpad area of FLASH
   
   // initialize write/erase pointer to any location in the scratchpad
   pwrite = (unsigned char xdata *) 0x0000;   

   EA_save = EA;                       // save interrupt status   
   EA = 0;                             // disable interrupts (precautionary)
   
   FLSCL |= 0x01;                      // enable FLASH writes/erases from
                                       // user software
   
   PSCTL = 0x07;                       // MOVX writes erase FLASH page
                                       // (SFLE set directing FLASH 
                                       // reads/writes/erases to the
                                       // scratchpad memory)

   *pwrite = 0;                        // initiate page erase

   PSCTL = 0;                          // MOVX writes target XRAM
                                       // (SFLE is cleared)
   
   FLSCL &= ~0x01;                     // disable FLASH writes/erases from
                                       // user software  
   
   EA = EA_save;                       // re-enable interrupts
   
   // PART D -- copy test string to the scratchpad page in FLASH 
      
   // initialize FLASH read pointer
   pread = (unsigned char code *) test_string;
   
   // initialize FLASH write pointer to the beginning of the scratchpad
   pwrite = 0x0000;                    

   EA_save = EA;                       // save interrupt status
   EA = 0;                             // disable interrupts (precautionary)
   
   FLSCL |= 0x01;                      // enable FLASH writes/erases from
                                       // user software
      
   PSCTL = 0x01;                       // MOVX writes target FLASH memory
                                          
   while (*pread != '\0') {            // copy until NULL is detected
      
      PSCTL |= 0x04;                   // set SFLE
      *pwrite = *pread;                // copy byte
      PSCTL &= ~0x04;                  // clear SFLE

      pread++;                         // advance pointers
      pwrite++;
   }

   PSCTL |= 0x04;                      // set SFLE
   *pwrite = '\0';                     // NULL-terminate string
   PSCTL &= ~0x04;                     // clear SFLE
   
   
   PSCTL = 0x00;                       // MOVX writes target XRAM
                                       
                                          
   FLSCL &= ~0x01;                     // disable FLASH writes/erases from
                                       // user software   

   EA = EA_save;                       // re-enable interrupts
   


   while (1);                          // spin forever
}