Differences

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--- code:i2c_eeprom [2008/11/27 02:34] – laurenceb
+++ code:i2c_eeprom [2009/03/20 04:50] (current) – laurenceb
@@ Line 18: / Line 18: @@
 	u16 timeout=1;
 	TWCR = (1<<TWINT)|(1<<TWSTA)|(1<<TWEN);	//send start
-	while (!(TWCR & (1<<TWINT)) && timeout);
+	while (!(TWCR & (1<<TWINT)) && timeout)
 		timeout++;							//wait for a start to be transmitted
 	if(!timeout)
@@ Line 31: / Line 31: @@
 	u16 timeout=1;
 	TWCR = (1<<TWINT)|(1<<TWEN)|(1<<TWSTO);
-	while (!(TWCR & (1<<TWSTO)) && timeout);//wait for stop to be sent
+	while (!(TWCR & (1<<TWSTO)) && timeout)	//wait for stop to be sent
 		timeout++;
 	if(!timeout)
@@ Line 42: / Line 42: @@
 	TWDR = c;								//load the data
 	TWCR = (1<<TWINT)|(1<<TWEN);
-	while (!(TWCR & (1<<TWINT)) && timeout);//wait for it to be sent
+	while (!(TWCR & (1<<TWINT)) && timeout)	//wait for it to be sent
 		timeout++;
 	if(!timeout)
@@ Line 50: / Line 50: @@
 }
-u08 i2cread(u08 AK)
+u08 i2cread(u08 ak)
 {
 	u16 timeout=1;
-	TWCR=AK;
+	TWCR=ak;
 	while ((!(TWCR & (1<<TWINT))) && timeout)
 		timeout++;							//wait for it to be recieved
@@ Line 94: / Line 94: @@
 	datasize--;
 	i2cstart();
-	i2cwrite(SLA_R|(((*address)>>15)&0x02));	//set read to the correct block
+	i2cwrite(SLA_R|((u08)((*address)>>15)&0x02));	//set read to the correct block
 	for(n=0;n<datasize;n++)						//the eeproms address pointer should have been setup already
 	{
@@ Line 105: / Line 105: @@
 		}This isn't needed on the Atmel chips*/
 	}
-	destination[datasize+1]=i2cread(_NAK_);		//send NAK for the last byte recieved
+	destination[datasize]=i2cread(_NAK_);		//send NAK for the last byte recieved
 	i2cstop();
+	(*address)++;
 }
@@ Line 112: / Line 113: @@
 u32 findtop()									//Find the address of record number where we enter painted eeprom
 {
-	u32 top=12*((u32)(((u32)1<<16)/12));		//half way through rounded down to nearest 12
+	u32 top=12*((u32)1<<13);					//half way through rounded down to 12
-	u08 n;
+	u08 n,endcond=TRUE;
-	u08 endcond=TRUE;							//used to solve the problem of running with n=0
+	u16 place=1<<13;
-	u16 place=5461;
 	for(n=14;endcond;)							//start by probing half way through - place is in records
 	{
@@ Line 122: / Line 122: @@
 			n--;								//need to decr here to get 1 byte resolution
 		else
-			endcond=FALSE;						//terminate the loop after completion
+			endcond=FALSE;						//terminate the loop after completion									//need to decr here to get 1 byte resolution
 		i2cstart();								//read the slave
 		i2cwrite(SLA_R);
 		if(i2cread(_NAK_)==MAGIC_NUMBER)		//see if its painted
-			place&=~(1<<n);						//set or clear the nth bit in the place holder
+			place&=~(1<<n);						//clear the nth bit in the place holder
-		else
+		if(n)
-			place|=(1<<n);
+			place|=(1<<(n-1));					//set the next bit
 		i2cstop();
+		if(place>10922)
+			place=10922;
 		top = 12*( (u32)place );				//place is in units of 12
 	}
+	set_address(&top);
+	i2cstart();
+	i2cwrite(SLA_R);
+	if(i2cread(_NAK_)!=MAGIC_NUMBER)			//check the location to make sure its blank
+		place++;
+	top = 12*( (u32)place );
 	return top;
 }
@@ Line 139: / Line 147: @@
 	u08 magic=MAGIC_NUMBER;						//magic is our painting value
 	u32 n=0;
-	set_address(&n);
+	for(;n<131072;n++/*n+=12*/)					//this writes every (12th) byte
-	for(;n<131072;n++)							//this writes every (12th) byte
 	{
-		/*set_address(&n);
+		/*
+		set_address(&n);
 		i2cwrite(magic);						//write the data
 		if((u08)n>243)							//our next n will be across a page boundary
@@ Line 149: / Line 157: @@
 			_delay_loop_2( (u16) ( (float)F_CPU*0.006/4.0 ) );//delay 6 ms for page write
 		}*/
-		if(!((u08)n))
+		if(!((u08)n))							//this code is for writing every byte
 		{
 			i2cstop();