S29GL512N SPANSION, S29GL512N Datasheet - Page 63

• Manufacturer Part Number: S29GL512N
• Description: Page Mode Flash Memory
• Manufacturer: SPANSION

S29GL-N_00_B3 October 13, 2006
Global Volatile Sector Protection Freeze Command Set
The PPB Program command is used to program, or set, a given PPB bit. Each PPB bit is indi-
vidually programmed (but is bulk erased with the other PPB bits). The specific sector address
(A24-A16 for S29GL512N, A23-A16 for S29GL256N, A22-A16 for S29GL128N) is written at
the same time as the program command. If the PPB Lock Bit is set to the freeze state, the
PPB Program command does not execute and the command times-out without programming
the PPB bit.
The All PPB Erase command is used to erase all PPB bits in bulk. There is no means for indi-
vidually erasing a specific PPB bit. Unlike the PPB program, no specific sector address is
required. However, when the All PPB Erase command is issued, all Sector PPB bits are erased
in parallel. If the PPB Lock Bit is set to freeze state, the ALL PPB Erase command does not
execute and the command times-out without erasing the PPB bits.
The device preprograms all PPB bits prior to erasing when issuing the All PPB Erase command.
Also note that the total number of PPB program/erase cycles has the same endurance as the
flash memory array.
The programming state of the PPB for a given sector can be verified by writing a PPB Status
Read Command to the device. This requires an initial access time latency.
The Non-Volatile Sector Protection Command Set Exit command must be issued after
the execution of the commands listed previously to reset the device to read mode.
Note that issuing the Non-Volatile Sector Protection Command Set Exit command
re-enables reads and writes for the main memory.
The Global Volatile Sector Protection Freeze Command Set permits the user to set the PPB
Lock Bit and reading the logic state of the PPB Lock Bit.
The Global Volatile Sector Protection Freeze Command Set Entry command sequence
must be issued prior to any of the commands listed following to enable proper command
execution.
Reads and writes from the main memory are not allowed.
The PPB Lock Bit Set command is used to set the PPB Lock Bit to the freeze state if it is cleared
either at reset or if the Password Unlock command was successfully executed. There is no PPB
Lock Bit Clear command. Once the PPB Lock Bit is set to the freeze state, it cannot be cleared
unless the device is taken through a power-on clear (for Persistent Protection Mode) or the
Password Unlock command is executed (for Password Protection Mode). If the Password Pro-
tection Mode Lock Bit is programmed, the PPB Lock Bit status is reflected as set to the freeze
state, even after a power-on reset cycle.
The programming state of the PPB Lock Bit can be verified by executing a PPB Lock Bit Status
Read command to the device.
The Global Volatile Sector Protection Freeze Command Set Exit command must be is-
sued after the execution of the commands listed previously to reset the device to read mode.
All PPB Erase Command
PPB Status Read Command
PPB Lock Bit Set Command
PPB Lock Bit Status Read Command
D a t a
S29GL-N MirrorBit™ Flash Family
S h e e t
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