S71PL512ND0 Datasheet, PDF (48/90 Pages) SPANSION – Two S29PL256N Devices (32 M x 16-Bit) CMOS 3.0-Volt only Simultaneous Read/Write, Page-Mode Flash Memory

Preliminary
Notes
1. Each PPB is individually programmed and all are erased in parallel.
2. Entry command disables reads and writes for the bank selected.
3. Reads within that bank return the PPB status for that sector.
4. Reads from other banks are allowed while writes are not allowed.
5. All Reads must be performed using the Asynchronous mode.
6. The specific sector addresses (A23 – A14 PL256N and A22 – A14 PL127N/PL129N) are writ-
ten at the same time as the program command.
7. If the PPB Lock Bit is set, the PPB Program or erase command does not execute and times-
out without programming or erasing the PPB.
8. There are no means for individually erasing a specific PPB and no specific sector address is
required for this operation.
9. Exit command must be issued after the execution which resets the device to read mode and
re-enables reads and writes for Bank A.
10. The programming state of the PPB for a given sector can be verified by writing a PPB Status
Read Command to the device as described by the flow chart below.
10.3
10.4
Dynamic Protection Bits
Dynamic Protection Bits are volatile and unique for each sector and can be individually modified.
DYBs only control the protection scheme for unprotected sectors that have their PPBs cleared
(erased to 1). By issuing the DYB Set or Clear command sequences, the DYBs are set (pro-
grammed to 0) or cleared (erased to 1), thus placing each sector in the protected or unprotected
state respectively. This feature allows software to easily protect sectors against inadvertent
changes yet does not prevent the easy removal of protection when changes are needed.
Notes
1. The DYBs can be set (programmed to 0) or cleared (erased to 1) as often as needed. When
the parts are first shipped, the PPBs are cleared (erased to 1) and upon power up or re-
set, the DYBs can be set or cleared depending upon the ordering option chosen.
2. If the option to clear the DYBs after power up is chosen, (erased to 1), then the sectorsmay
be modified depending upon the PPB state of that sector.
3. The sectors would be in the protected state If the option to set the DYBs after power up is
chosen (programmed to 0).
4. It is possible to have sectors that are persistently locked with sectors that are left in the
dynamic state.
5. The DYB Set or Clear commands for the dynamic sectors signify protected or unprotected
state of the sectors respectively. However, if there is a need to change the status of the per-
sistently locked sectors, a few more steps are required. First, the PPB Lock Bit must be
cleared by either putting the device through a power-cycle, or hardware reset. The PPBs can
then be changed to reflect the desired settings. Setting the PPB Lock Bit once again locks
the PPBs, and the device operates normally again.
6. To achieve the best protection, it is recommended to execute the PPB Lock Bit Set command
early in the boot code and protect the boot code by holding WP# = V_IL. Note that the PPB
and DYB bits have the same function when WP#/ACC = V_HH as they do when WP#/
ACC = V_IH.
Persistent Protection Bit Lock Bit
The Persistent Protection Bit Lock Bit is a global volatile bit for all sectors. When set (programmed
to 0), this bit locks all PPB and when cleared (programmed to 1), unlocks each sector. There is
only one PPB Lock Bit per device.
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S29PL-N MirrorBit™ Flash Family
S29PL-N_M0_A4 November 23, 2005