D a t a S h e e t ( P r e l i m i n a r y )
Software Functions and Sample Code
Table 7.7 Write Buffer Program
(LLD Functions Used = lld_WriteToBufferCmd, lld_ProgramBufferToFlashCmd)
Cycle
Description
Operation
Write
Byte Address
Base + AAAh
Base + 555h
Word Address
Base + 555h
Base + 2AAh
Data
1
2
3
4
Unlock
Unlock
00AAh
0055h
0025h
Write
Write Buffer Load Command
Write Word Count
Write
Sector Address
Sector Address
Write
Word Count (N–1)h
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 (available on 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
/* flash destination address
/* word count (minus 1)
/* write unlock cycle 1
/* write unlock cycle 2
*/
*/
UINT16 *dst = destination_of_data;
UINT16 wc
= words_to_program -1;
*/
*/
*/
*( (UINT16 *)base_addr + 0x555 ) = 0x00AA;
*( (UINT16 *)base_addr + 0x2AA ) = 0x0055;
*( (UINT16 *)sector_address )
*( (UINT16 *)sector_address )
= 0x0025;
= wc;
/* write write buffer load command */
/* write word count (minus 1) */
for (i=0;i<=wc;i++)
{
*dst++ = *src++; /* ALL dst MUST BE in same Write Buffer */
}
*( (UINT16 *)sector_address )
/* poll for completion */
= 0x0029;
/* write confirm command
*/
/* 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
28
S29GL-P MirrorBit® Flash Family
S29GL-P_00_A7 November 8, 2007
SPANSION [ SPANSION ]
