Sir,
I am new to Microcontroller.I have a doubt in the below program.It is a silly doubt but i am not able to get it. Here why we are incrementing the value of variable called value we should store the same value 0 in segmentA and then copy that to SegmentB.Please help me.
// MSP-FET430P120 Demo - Flash In-System Programming, Copy SegA to SegB
//
// Description: This program first erases flash seg A, then it increments all
// values in seg A, then it erases seg B, then copies seg A to seg B.
// Assumed MCLK 550kHz - 900kHz.
// //* Set Breakpoint on NOP in the Mainloop to avoid Stressing Flash *//
//
// MSP430F123(2)
// -----------------
// /|\| XIN|-
// | | |
// --|RST XOUT|-
// | |
//
// M. Mitchell
// Texas Instruments Inc.
// Feb 2005
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.21A
//******************************************************************************
#include <msp430x12x2.h>
char value; // 8-bit value to write to segment A
// Function prototypes
void write_SegA (char value);
void copy_A2B (void);
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop watchdog timer
FCTL2 = FWKEY + FSSEL0 + FN0; // MCLK/2 for Flash Timing Generator
value = 0; // initialize value
while(1) // Repeat forever
{
write_SegA(value++); // Write segment A, increment value
copy_A2B(); // Copy segment A to B
_NOP(); // SET BREAKPOINT HERE
}
}
void write_SegA (char value)
{
char *Flash_ptr; // Flash pointer
unsigned int i;
Flash_ptr = (char *) 0x1080; // Initialize Flash pointer
FCTL1 = FWKEY + ERASE; // Set Erase bit
FCTL3 = FWKEY; // Clear Lock bit
*Flash_ptr = 0; // Dummy write to erase Flash segment
FCTL1 = FWKEY + WRT; // Set WRT bit for write operation
for (i=0; i<128; i++)
{
*Flash_ptr++ = value; // Write value to flash
}
FCTL1 = FWKEY; // Clear WRT bit
FCTL3 = FWKEY + LOCK; // Set LOCK bit
}
void copy_A2B (void)
{
char *Flash_ptrA; // Segment A pointer
char *Flash_ptrB; // Segment B pointer
unsigned int i;
Flash_ptrA = (char *) 0x1080; // Initialize Flash segment A pointer
Flash_ptrB = (char *) 0x1000; // Initialize Flash segment B pointer
FCTL1 = FWKEY + ERASE; // Set Erase bit
FCTL3 = FWKEY; // Clear Lock bit
*Flash_ptrB = 0; // Dummy write to erase Flash segment B
FCTL1 = FWKEY + WRT; // Set WRT bit for write operation
for (i=0; i<128; i++)
{
*Flash_ptrB++ = *Flash_ptrA++; // copy value segment A to segment B
}
FCTL1 = FWKEY; // Clear WRT bit
FCTL3 = FWKEY + LOCK; // Set LOCK bit
}