52
S29PL-N MirrorBit
Flash Family
S29PL-N_00_A5 June 6, 2007
D a t a
S h e e t
( P r e l i m i n a r y )
10.2
Customer Secured Silicon Sector
The Customer Secured Silicon Sector is typically shipped unprotected (DQ6 set to
0
), allowing customers to
utilize that sector in any manner they choose. If the security feature is not required, the Customer Secured
Silicon Sector can be treated as an additional Flash memory space.
Please note the following:
Once the Customer Secured Silicon Sector area is protected, the Customer Indicator Bit is permanently
set to
1
.
The Customer Secured Silicon Sector can be read any number of times, but can be programmed and
locked only once. The Customer Secured Silicon Sector lock must be used with caution as once locked,
there is no procedure available for unlocking the Customer Secured Silicon Sector area and none of the
bits in the Customer Secured Silicon Sector memory space can be modified in any way.
The accelerated programming (ACC) and unlock bypass functions are
not
available when programming the
Customer Secured Silicon Sector, but are available when reading in Banks B through D.
Once the Customer 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 and 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 the Command Definition Tables:
Table 12.1,
Memory Array Commands
on page 66
,
Table 12.2,
Sector Protection Commands
on page 68
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.