D at a
S hee t
(Adva nce
In for m ation)
Software Functions and Sample Code
Table 7.6
Single Word/Byte Program
(LLD Function = lld_ProgramCmd)
Cycle
Unlock Cycle 1
Unlock Cycle 2
Program Setup
Program
Note
Base = Base Address.
Operation
Write
Write
Write
Write
Byte Address
Base + AAAh
Base + 555h
Base + AAAh
Byte Address
Word Address
Base + 555h
Base + 2AAh
Base + 555h
Word Address
Data
00AAh
0055h
00A0h
Data
The following is a C source code example of using the single word 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: Program Command
*/
*( (UINT16 *)base_addr + 0x555 )
*( (UINT16 *)base_addr + 0x2AA )
*( (UINT16 *)base_addr + 0x555 )
*( (UINT16 *)pa )
/* Poll for program completion */
=
=
=
=
0x00AA;
0x0055;
0x00A0;
data;
/*
/*
/*
/*
write
write
write
write
unlock cycle 1
unlock cycle 2
program setup command
data to be programmed
*/
*/
*/
*/
7.7.2
Write Buffer Programming
Write Buffer Programming allows the system to write a maximum of 32 words in one programming operation.
This results in a faster effective word programming time than the standard “word” programming algorithms.
The Write Buffer Programming command sequence is initiated by first writing two unlock cycles. This is
followed by a third write cycle containing the Write Buffer Load command written at the Sector Address in
which programming occurs. At this point, the system writes the number of “word locations minus 1” that are
loaded into the page buffer at the Sector Address in which programming occurs. This tells the device how
many write buffer addresses are loaded with data and therefore when to expect the “Program Buffer to Flash”
confirm command. The number of locations to program cannot exceed the size of the write buffer or the
operation aborts. (Number loaded = the number of locations to program minus 1. For example, if the system
programs 6 address locations, then 05h should be written to the device.)
The system then writes the starting address/data combination. This starting address is the first address/data
pair to be programmed, and selects the “write-buffer-page” address. All subsequent address/data pairs must
fall within the elected-write-buffer-page.
The “write-buffer-page” is selected by using the addresses A
MAX
–A5.
The “write-buffer-page” addresses must be the same for all address/data pairs loaded into the write buffer.
(This means Write Buffer Programming cannot be performed across multiple “write-buffer-pages.” This also
means that Write Buffer Programming cannot be performed across multiple sectors. If the system attempts to
load programming data outside of the selected “write-buffer-page”, the operation ABORTs.)
After writing the Starting Address/Data pair, the system then writes the remaining address/data pairs into the
write buffer.
Note that if a Write Buffer address location is loaded multiple times, the “address/data pair” counter is
decremented for every data load operation. Also, the last data loaded at a location before the “Program Buffer
to Flash” confirm command is programmed into the device. It is the software's responsibility to comprehend
ramifications of loading a write-buffer location more than once. The counter decrements for each data load
operation, NOT for each unique write-buffer-address location. Once the specified number of write buffer
locations have been loaded, the system must then write the “Program Buffer to Flash” command at the Sector
Address. Any other address/data write combinations abort the Write Buffer Programming operation. The
device goes “busy.” The Data Bar polling techniques should be used while monitoring the last address
location loaded into the write buffer. This eliminates the need to store an address in memory because the
system can load the last address location, issue the program confirm command at the last loaded address
location, and then data bar poll at that same address. DQ7, DQ6, DQ5, DQ2, and DQ1 should be monitored
to determine the device status during Write Buffer Programming.
November 21, 2006 S29GL-P_00_A3
S29GL-P MirrorBit
TM
Flash Family
21
SPANSION [ SPANSION ]
