Internal Flash Programming (PowerPC)?

Hello all,

I have to program the internal flash (it is called UC3F) of an MPC563
PowerPC. After having read the Reference Manual's chapter three times,
I still don't understand fully how to write a sequence of bytes to the
flash. I am sure that it is not that difficult, but it's the first
time I have this kind of task.

From what I understand:

In order to rewrite the flash, you must first erase it.

Writing the Flash is done via a Hardware State Machine.

I have found this code snippets in
http://blog.gmane.org/gmane.comp.hardware.motorola.microcontrollers/month=20030901

#define C3F_ADDR       0x002FC800   // C3F register base address
#define UC3F_A   (*((volatile unsigned long *)(0x00000000)))  // flash
memory location

....
 C3F[0] = (struct C3F_tag *)(C3F_ADDR);

//erase
 C3F[0]->C3FMCR.PROTECT = 0; //Disable Protect
 C3F[0]->C3FCTL.PE = 1;
 C3F[0]->C3FCTL.SES = 1; 
 UC3F_A = 0xffffffff; //garbage value
 C3F[0]->C3FCTL.EHV = 1; 
 while( C3F[0]->C3FCTL.HVS != 0 );
 while(C3F[0]->C3FCTL.PEGOOD != 1);

 C3F[0]->C3FCTL.EHV = 0;
 C3F[0]->C3FCTL.SES = 0;

//write  
 C3F[0]->C3FMCR.PROTECT = 0;
 C3F[0]->C3FCTL.SES = 1; 
 C3F[0]->C3FCTL.PE = 0;
 UC3F_A = 0xCCCCCCCC;       
 C3F[0]->C3FCTL.EHV = 1;  
 while( C3F[0]->C3FCTL.HVS != 0 );

 while(C3F[0]->C3FCTL.PEGOOD != 1);

 C3F[0]->C3FCTL.EHV = 0;
 C3F[0]->C3FCTL.SES = 0;


I understand the 'frame' of the erase and write blocks: First the
registers are set to initiate the erase/write process, then comes the
'interesting' middle part. Finally, you have to poll for two status
bits and reset two initiating bits.

But I don't understand this middle part. How do I determine the flash
address to be written to, and how do I determine the content (byte,
int, long or whatever) to write to that address? In the code above,
UC3F_A is the first memory location of the flash. Does this mean that

UC3F_A = 0xCCCCCCCC; 

writes 0xCCCCCCCC to this memory location?

The processor manual implies to me that the first write determines the
address and the second determines the data, but I probably don't
understand it:

"Programming write � A successful write to the array location to be
programmed.
This write updates the program data latch with the information to be
programmed.
In addition, the addressof the first programming write is latched in
the UC3F
memory interface block. All accesses of the array after the first
write are to the
same address regardless of the address provided. Thus the locations
accessed after
the first programming write are limited to the location to be
programmed."

Anyway, the code above only writes to one flash memory location. Does
this mean, I have to repeat the whole sequence to write to the next
location?

Any help would be great.


Best regards


Johannes