S29PL-J SPANSION [SPANSION], S29PL-J Datasheet - Page 50

• Manufacturer Part Number: S29PL-J
• Description: CMOS 3.0 Volt-only, Simultaneous-Read/Write Flash Memory with Enhanced VersatileIO Control
• Manufacturer: SPANSION [SPANSION]

13.3
13.4
48
13.3.1
Write Protect (WP#)
High Voltage Sector Protection
Persistent Protection Bit Lock
The Write Protect feature provides a hardware method of protecting the upper two and lower two sectors
without using V
Voltage Sector Protection on page 48
If the system asserts V
outermost 4 Kword sectors on both ends of the flash array independent of whether it was previously protected
or unprotected.
If the system asserts V
whether they were last set to be protected or unprotected. That is, sector protection or unprotection for these
sectors depends on whether they were last protected or unprotected using the method described in the
Voltage Sector Protection on page
Note that the WP#/ACC pin must not be left floating or unconnected; inconsistent behavior of the device may
result.
The Persistent Protection Bit (PPB) Lock is a volatile bit that reflects the state of the Password Mode Locking
Bit after power-up reset. If the Password Mode Lock Bit is also set after a hardware reset (RESET# asserted)
or a power-up reset, the ONLY means for clearing the PPB Lock Bit in Password Protection Mode is to issue
the Password Unlock command. Successful execution of the Password Unlock command clears the PPB
Lock Bit, allowing for sector PPBs modifications. Asserting RESET#, taking the device through a power-on
reset, or issuing the PPB Lock Bit Set command sets the PPB Lock Bit to a “1” when the Password Mode
Lock Bit is not set.
If the Password Mode Locking Bit is not set, including Persistent Protection Mode, the PPB Lock Bit is cleared
after power-up or hardware reset. The PPB Lock Bit is set by issuing the PPB Lock Bit Set command. Once
set the only means for clearing the PPB Lock Bit is by issuing a hardware or power-up reset. The Password
Unlock command is ignored in Persistent Protection Mode.
Sector protection and unprotection may also be implemented using programming equipment. The procedure
requires high voltage (V
this procedure. Note that for sector unprotect, all unprotected sectors must first be protected prior to the first
sector write cycle.
ID
. This function is provided by the WP# pin and overrides the previously discussed
IL
IH
D a t a
ID
on the WP#/ACC pin, the device disables program and erase functions in the two
on the WP#/ACC pin, the device reverts the upper two and lower two sectors to
) to be placed on the RESET# pin. Refer to
S h e e t
48.
method.
S29PL-J
( A d v a n c e
I n f o r m a t i o n )
Figure 13.1 on page 49
S29PL-J_00_A9 September 22, 2006
for details on
High
High