Data
Sheet
(Advan ce
Infor m a tio n)
Once the Secured Silicon Sector is locked and verified, the system must write the Exit Secured Silicon
Sector Region command sequence which return the device to the memory array at sector 0.
10.3
Secured Silicon Sector Entry/Exit Command Sequences
The system can access the Secured Silicon Sector region by issuing the three-cycle Enter Secured Silicon
Sector command sequence. The device continues to access the Secured Silicon Sector region until the
system issues the four-cycle Exit Secured Silicon Sector command sequence.
See Command Definition Table [Secured Silicon Sector Command Table, Appendix
through
for address and data requirements for both command
sequences.
The Secured Silicon Sector Entry Command allows the following commands to be executed
Read customer and factory Secured Silicon areas
Program the customer Secured Silicon Sector
After the system has written the Enter Secured Silicon Sector command sequence, it may read the Secured
Silicon Sector by using the addresses normally occupied by sector SA0 within the memory array. This mode
of operation continues until the system issues the Exit Secured Silicon Sector command sequence, or until
power is removed from the device.
Software Functions and Sample Code
The following are C functions and source code examples of using the Secured Silicon Sector Entry, Program,
and exit commands. Refer to the
Spansion Low Level Driver User’s Guide
www.spansion.com)
for general information on Spansion Flash memory software development guidelines.
Table 10.2
Secured Silicon Sector Entry
(LLD Function = lld_SecSiSectorEntryCmd)
Cycle
Unlock Cycle 1
Unlock Cycle 2
Entry Cycle
Note
Base = Base Address.
Operation
Write
Write
Write
Byte Address
Base + AAAh
Base + 555h
Base + AAAh
Word Address
Base + 555h
Base + 2AAh
Base + 555h
Data
00AAh
0055h
0088h
/* Example: SecSi Sector
*( (UINT16 *)base_addr
*( (UINT16 *)base_addr
*( (UINT16 *)base_addr
Entry Command */
+ 0x555 ) = 0x00AA;
+ 0x2AA ) = 0x0055;
+ 0x555 ) = 0x0088;
/* write unlock cycle 1
/* write unlock cycle 2
/* write Secsi Sector Entry Cmd
*/
*/
*/
Table 10.3
Secured Silicon Sector Program
(LLD Function = lld_ProgramCmd)
Cycle
Unlock Cycle 1
Unlock Cycle 2
Program Setup
Program
Note
Base = Base Address.
/* Once in the SecSi Sector mode, you program */
/* words using the programming algorithm.
*/
Operation
Write
Write
Write
Write
Byte Address
Base + AAAh
Base + 555h
Base + AAAh
Word Address
Word Address
Base + 555h
Base + 2AAh
Base + 555h
Word Address
Data
00AAh
0055h
00A0h
Data Word
46
S29GL-P MirrorBit
TM
Flash Family
S29GL-P_00_A3 November 21, 2006
SPANSION [ SPANSION ]
