D a t a S h e e t
Autoselect Command Sequence
The autoselect command sequence allows the host system to access the manufacturer and
device codes, and determine whether or not a sector is protected. Table 12 on page 63 and
Table 14 on page 65 show the address and data requirements. This method is an alternative
to that shown in Table 5 on page 37, which is intended for PROM programmers and requires
VID on address pin A9. The autoselect command sequence may be written to an address that
is either in the read or erase-suspend-read mode. The autoselect command may not be writ-
ten while the device is actively programming or erasing.
The autoselect command sequence is initiated by first writing two unlock cycles. This is fol-
lowed by a third write cycle that contains the autoselect command. The device then enters
the autoselect mode. The system may read at any address any number of times without ini-
tiating another autoselect command sequence:
A read cycle at address XX00h returns the manufacturer code.
Three read cycles at addresses 01h, 0Eh, and 0Fh return the device code.
A read cycle to an address containing a sector address (SA), and the address 02h on A7–
A0 in word mode returns 01h if the sector is protected, or 00h if it is unprotected.
The system must write the reset command to return to the read mode (or erase-sus-
pend-read mode if the device was previously in Erase Suspend).
Enter Secured Silicon Sector/Exit Secured Silicon
Sector Command Sequence
The Secured Silicon Sector region provides a secured data area containing an 8-word/16-byte
random Electronic Serial Number (ESN). The system can access the Secured Silicon Sector
region by issuing the three-cycle Enter Secured Silicon Sector command sequence. The de-
vice continues to access the Secured Silicon Sector region until the system issues the
four-cycle Exit Secured Silicon Sector command sequence. The Exit Secured Silicon Sector
command sequence returns the device to normal operation. Table 12 on page 63 shows the
address and data requirements for both command sequences. See also “Secured Silicon Sec-
tor Flash Memory Region” for further information. Note that the ACC function and unlock
bypass modes are not available when the Secured Silicon Sector is enabled.
Word Program Command Sequence
Programming is a four-bus-cycle operation. The program command sequence is initiated by
writing two unlock write cycles, followed by the program set-up command. The program ad-
dress and data are written next, which in turn initiate the Embedded Program algorithm. The
system is not required to provide further controls or timings. The device automatically pro-
vides internally generated program pulses and verifies the programmed cell margin. Table 12
on page 63 and Table 14 on page 65 show the address and data requirements for the word
program command sequence.
When the Embedded Program algorithm is complete, the device then returns to the read
mode and addresses are no longer latched. The system can determine the status of the pro-
gram operation by using DQ7 or DQ6. Refer to the Write Operation Status section for
information on these status bits.
Any commands written to the device during the Embedded Program Algorithm are ignored.
Note that the Secured Silicon Sector, autoselect, and CFI functions are unavailable
when a program operation is in progress. Note that a hardware reset immediately ter-
minates the program operation. The program command sequence should be reinitiated once
the device has returned to the read mode, to ensure data integrity.
Programming is allowed in any sequence of address locations and across sector boundaries.
Programming to the same word address multiple times without intervening erases (incremen-
S29GL-N_00_B3 October 13, 2006
S29GL-N MirrorBit™ Flash Family
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SPANSION [ SPANSION ]
