D at a
S hee t
(Adva nce
In for m ation)
Software Functions and Sample Code
Table 7.7
Write Buffer Program
(LLD Functions Used = lld_WriteToBufferCmd, lld_ProgramBufferToFlashCmd)
Cycle
1
2
3
4
Description
Unlock
Unlock
Write Buffer Load Command
Write Word Count
Operation
Write
Write
Write
Write
Byte Address
Base + AAAh
Base + 555h
Word Address
Base + 555h
Base + 2AAh
Data
00AAh
0055h
0025h
Word Count (N–1)h
Sector Address
Sector Address
Number of words (N) loaded into the write buffer can be from 1 to 32 words (1 to 64 bytes).
5 to 36
Last
Load Buffer Word N
Write Buffer to Flash
Write
Write
Program Address, Word N
Sector Address
Word N
0029h
Notes
1. Base = Base Address.
2. Last = Last cycle of write buffer program operation; depending on number of words written, the total number of cycles may be from 6 to
37.
3. For maximum efficiency, it is recommended that the write buffer be loaded with the highest number of words (N words) possible.
The following is a C source code example of using the write buffer program function. Refer to the
Spansion
Low Level Driver User’s Guide
www.spansion.com)
for general information on Spansion Flash
memory software development guidelines.
/* Example: Write Buffer Programming Command
*/
/* NOTES: Write buffer programming limited to 16 words. */
/*
All addresses to be written to the flash in
*/
/*
one operation must be within the same flash
*/
/*
page. A flash page begins at addresses
*/
/*
evenly divisible by 0x20.
*/
UINT16 *src = source_of_data;
/* address of source data
*/
UINT16 *dst = destination_of_data;
/* flash destination address
*/
UINT16 wc
= words_to_program -1;
/* word count (minus 1)
*/
*( (UINT16 *)base_addr + 0x555 ) = 0x00AA;
/* write unlock cycle 1
*/
*( (UINT16 *)base_addr + 0x2AA ) = 0x0055;
/* write unlock cycle 2
*/
*( (UINT16 *)sector_address )
= 0x0025;
/* write write buffer load command */
*( (UINT16 *)sector_address )
= wc;
/* write word count (minus 1)
*/
loop:
*dst = *src; /* ALL dst MUST BE SAME PAGE */ /* write source data to destination */
dst++;
/* increment destination pointer
*/
src++;
/* increment source pointer
*/
if (wc == 0) goto confirm
/* done when word count equals zero */
wc--;
/* decrement word count
*/
goto loop;
/* do it again
*/
confirm:
*( (UINT16 *)sector_address )
= 0x0029;
/* write confirm command
*/
/* poll for completion */
/* Example: Write Buffer Abort Reset */
*( (UINT16 *)addr + 0x555 ) = 0x00AA;
*( (UINT16 *)addr + 0x2AA ) = 0x0055;
*( (UINT16 *)addr + 0x555 ) = 0x00F0;
/* write unlock cycle 1
/* write unlock cycle 2
/* write buffer abort reset
*/
*/
*/
November 21, 2006 S29GL-P_00_A3
S29GL-P MirrorBit
TM
Flash Family
23
SPANSION [ SPANSION ]
