S71PL129JC0 Datasheet, PDF (53/149 Pages) SPANSION – Stacked Multi-Chip Product (MCP) Flash Memory

Advance Information
to correctly match a password. If the command is issued before the 2 µs execu-
tion window for each portion of the unlock, the command will be ignored.
Once the Password Unlock command is entered, the RY/BY# indicates that the
device is busy. Approximately 1 µs is required for each portion of the unlock. Once
the first portion of the password unlock completes (RY/BY# is not low or DQ6
does not toggle when read), the next part of the password is written. The system
must thus monitor RY/BY# or the status bits to confirm when to write the next
portion of the password. Seven cycles are required to successfully clear the PPB
Lock Bit.
PPB Program Command
The PPB Program command is used to program, or set, a given PPB. Each PPB is
individually programmed (but is bulk erased with the other PPBs). The specific
sector address (A22–A12) are written at the same time as the program command
60h with A6 = 0. If the PPB Lock Bit is set and the corresponding PPB is set for
the sector, the PPB Program command will not execute and the command will
time-out without programming the PPB.
After programming a PPB, two additional cycles are needed to determine whether
the PPB has been programmed with margin. If the PPB has been programmed
without margin, the program command should be reissued to improve the pro-
gram margin. Also note that the total number of PPB program/erase cycles is
limited to 100 cycles. Cycling the PPBs beyond 100 cycles is not guaranteed.
The PPB Program command does not follow the Embedded Program algorithm.
All PPB Erase Command
The All PPB Erase command is used to erase all PPBs in bulk. There is no means
for individually erasing a specific PPB. Unlike the PPB program, no specific sector
address is required. However, when the PPB erase command is written all Sector
PPBs are erased in parallel. If the PPB Lock Bit is set the ALL PPB Erase command
will not execute and the command will time-out without erasing the PPBs. After
erasing the PPBs, two additional cycles are needed to determine whether the PPB
has been erased with margin. If the PPBs has been erased without margin, the
erase command should be reissued to improve the program margin.
It is the responsibility of the user to preprogram all PPBs prior to issuing the All
PPB Erase command. If the user attempts to erase a cleared PPB, over-erasure
may occur making it difficult to program the PPB at a later time. Also note that
the total number of PPB program/erase cycles is limited to 100 cycles. Cycling the
PPBs beyond 100 cycles is not guaranteed.
DYB Write Command
The DYB Write command is used for setting the DYB, which is a volatile bit that
is cleared at reset. There is one DYB per sector. If the PPB is set, the sector is
protected regardless of the value of the DYB. If the PPB is cleared, setting the
DYB to a 1 protects the sector from programs or erases. Since this is a volatile
bit, removing power or resetting the device will clear the DYBs. The bank address
is latched when the command is written.
PPB Lock Bit Set Command
The PPB Lock Bit set command is used for setting the DYB, which is a volatile bit
that is cleared at reset. There is one DYB per sector. If the PPB is set, the sector
is protected regardless of the value of the DYB. If the PPB is cleared, setting the
June 4, 2004 S29PL129J_MCP_00_A0
S29PL129J for MCP
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