Writing Information Memory (Segment A)

#include"headers.h"

/*
 * app_flash.c
 *
 *  Created on: 05-Dec-2013
 *      Author: Rajni Bhojani
 */

/*
 * 		WRITE MODE
 * 			  BLKWRT   WRT
 * 				0		1			BYTE/WORD WRITE
 * 				1		1			BLOCK WRITE
 *
 *		ERASE FLASH MEMORY
 *			MERAS	ERASE
 *				0		1			SEGMENT ERASE
 *				1		0			MASS ERASE ALL MAIN MEMORY SEGMENT
 *				1		1			ERASE ALL FLASH MEMORY
 *
 *		IN ERASE MODE ANY WRITE CAN ERASE WHOLE SEGEMNT OR AS PER SELECTION.
 *		WITHOUT ANY CONFIGURATION ANY WRITE OPERATION IGNORED
 *
 *		As per data sheet flash controller Clock Frequency should be 257-476 KHz.
 *
 */

#define BLOCK_SIZE					64
#define SEGMENT_A_START_ADDRESS		0x1000
#define SEGMENT_B_START_ADDRESS		0x1080
#define SEGMENT_A_SIZE				0X80
#define SEGMENT_B_SIZE				0X80

#define FLW_KEY						0xA500				// key that needed at every write cycle
#define FL_MCLK						0x0040				// MCLK for flash controller
#define FL_DIV20					0x0013				// clock is devided by value + 1

#define SET_LOCK					FCTL3 = FLW_KEY + LOCK				// Lock the any write or erasing operation(ignored) to flash.
#define CLEAR_LOCK					FCTL3 = FLW_KEY						// Clear the lock to enable write and erasing.

#define WRITE_BYTE_MODE				FCTL1 = FLW_KEY + WRT				// set write byte or word mode
#define WRITE_BLOCK_MODE			FCTL1 = FLW_KEY + BLKWRT + WRT		// set block write mode
#define CLEAR_WRITEBIT				FCTL1 = FLW_KEY

#define SEGMENT_ERASE				FCTL1 = FLW_KEY +ERASE				// Set segment erase mode
#define MAINMEMORY_ERASE			FCTL1 = FLW_KEY +MERAS				// Set main memory erase mode
#define FLASH_ERASE					FCTL1 = ERASE + MERAS				// Set flash erase mode

#define WAIT_FORLOCK				while((FCTL3 & LOCK))

#define WAIT_FORNEXTBYTE			while(!(FCTL3 & WAIT))				// During block write cycle
																		// After every byte write we have to wait for this byte set
																		// This says that i am ready for nex byte

/************************************************************************************************
 * 		FUNCTION		:	InitFlashController
 * 		DISCRIPTION		:	INIT THE FLASH CONTROLLER TO CONTROLL THE OPERATION (WRITE/ERASE).
 ************************************************************************************************
 */
void InitFlashController() {

	FCTL2 = FLW_KEY + FL_MCLK + FL_DIV20;						// Clock will be around 400 KHz
																// MCLK is selected
}


/************************************************************************************************
 * 		FUNCTION		:	Flash_WriteByte
 * 		DISCRIPTION		:	This can modify the byte in flash memory
 *
 * 		NOTE			:	CAN ONLY DO THE BIT 1 VALUE TO 0 VALUE IF YOU WNT TO DO THE REVERSE
 * 							ONLY WAY TO ERASE THE SEGMENT AND REWRITE THE SEGMENT
 * 							EXAMPLE : 0XFF CAN BE TRANSFERED TO 0XAA, OR ANY OTHER VALUE BUT
 * 									  0X00 CAN NOT BE TRANSFERED TO ANY VALUE
 ************************************************************************************************
 */
void Flash_WriteByte(unsigned int address, unsigned char Write_Data) {

	__disable_interrupt();

	WRITE_BYTE_MODE;
	CLEAR_LOCK;
	*((unsigned char*)address) = Write_Data;

	SET_LOCK;
	__enable_interrupt();
}


/************************************************************************************************
 * 		FUNCTION		:	Flash_WriteBlock
 * 		DISCRIPTION		:	TO MODIFY VALUE OF THE ENTIRE BLOCK
 ************************************************************************************************
 */
void Flash_WriteBlock(unsigned int address, unsigned char* Write_Data) {

	unsigned char i;

	__disable_interrupt();

	WRITE_BLOCK_MODE;
	CLEAR_LOCK;

	for(i=BLOCK_SIZE; i; i--) {
		Flash_WriteByte(address++, *(Write_Data++));
	}

	SET_LOCK;
	__enable_interrupt();
}


/************************************************************************************************
 * 		FUNCTION		:	Erase_Segment
 * 		DISCRIPTION		:	TO ERASE SEGMENT YOU HAVE TO PASS THE ANY ADDRESS FALL WITHIN THAT
 * 							segment RANGE
 ************************************************************************************************
 */
void Erase_Segment(unsigned int segment_address) {

	__disable_interrupt();

	SEGMENT_ERASE;
	CLEAR_LOCK;

	*((unsigned char*)segment_address) = 0;		// will erase segment

	SET_LOCK;
}


/************************************************************************************************
 * 		FUNCTION		:	ModifyInfoASegment
 * 		DISCRIPTION		:	TO MODIFY THE SEGMENT A
 ************************************************************************************************
 */
void ModifyInfoASegment(unsigned char* Info_MemoryBuffer) {

	Erase_Segment(SEGMENT_A_START_ADDRESS);

	Flash_WriteBlock(SEGMENT_A_START_ADDRESS, Info_MemoryBuffer);
	Flash_WriteBlock(SEGMENT_A_START_ADDRESS+BLOCK_SIZE, Info_MemoryBuffer+BLOCK_SIZE);
}


/************************************************************************************************
 * 		FUNCTION		:	ModifyInfoBSegment
 * 		DISCRIPTION		:	TO MODIFY THE SEGMENT B
 ************************************************************************************************
 */
void ModifyInfoBSegment(unsigned char *Info_MemoryBuffer) {

	Erase_Segment(SEGMENT_B_START_ADDRESS);

	Flash_WriteBlock(SEGMENT_B_START_ADDRESS, Info_MemoryBuffer);
	Flash_WriteBlock(SEGMENT_B_START_ADDRESS+BLOCK_SIZE, Info_MemoryBuffer+BLOCK_SIZE);
}


/************************************************************************************************
 * 		FUNCTION		:	ModifyInfoBSegment
 * 		DISCRIPTION		:	TO MODIFY INFO SEGMENT
 ************************************************************************************************
 */
void WriteInfoSegment(unsigned char* Info_MemoryBuffer) {

	ModifyInfoASegment(Info_MemoryBuffer);
	ModifyInfoBSegment(Info_MemoryBuffer + SEGMENT_A_SIZE);
}