Document Number: 002-00856 Rev. *E
S29JL064J
10.3
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. The autoselect command sequence may be written to an address within a bank that is either in the read or
erase-suspend-read mode. The autoselect command may not be written while the device is actively programming or erasing in
another bank.
The autoselect command sequence is initiated by first writing two unlock cycles. This is followed by a third write cycle that contains
the bank address and the autoselect command. The bank then enters the autoselect mode. The system may read any number of
autoselect codes without re-initiating the command sequence.
shows the address and data requirements. To determine sector protection information, the system must write to
the appropriate bank address (BA) and sector address (SA).
shows the address range and bank number
associated with each sector.
The system must write the reset command to return to the read mode (or erase-suspend-read mode if the bank was previously in
Erase Suspend).
10.4
Enter Secured Silicon Region/Exit Secured Silicon Region Command
Sequence
The system can access the Secured Silicon Region by issuing the three-cycle Enter Secured Silicon Region command sequence.
The device continues to access the Secured Silicon Region until the system issues the four-cycle Exit Secured Silicon Region
command sequence. The Exit Secured Silicon Region command sequence returns the device to normal operation. The Secured
Silicon Region is not accessible when the device is executing an Embedded Program or embedded Erase algorithm.
shows the address and data requirements for both command sequences. See also
for
further information.
Note that the ACC function and unlock bypass modes are not available when the Secured Silicon Region is
enabled.
10.5
Byte/Word Program Command Sequence
The system may program the device by word or byte, depending on the state of the BYTE# pin. 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 address 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 provides internally generated program pulses and
verifies the programmed cell margin.
shows the address and data requirements for the byte program command
sequence.
When the Embedded Program algorithm is complete, that bank then returns to the read mode and addresses are no longer latched.
The system can determine the status of the program operation by using DQ7, DQ6, or RY/BY#. Refer to
for information on these status bits.
Any commands written to the device during the Embedded Program Algorithm are ignored.
Note that a
hardware reset
immediately
terminates the program operation. The program command sequence should be reinitiated once that bank has returned to the read
mode, to ensure data integrity.
Note that the Secured Silicon Region, autoselect, and CFI functions are unavailable when a program
operation is in progress.
Programming is allowed in any sequence and across sector boundaries.
A bit cannot be programmed from 0 back to a 1.
Attempting to do so may cause that bank to set DQ5 = 1, or cause the DQ7 and DQ6 status bits to indicate the operation was
successful. However, a succeeding read will show that the data is still 0. Only erase operations can convert a 0 to a
1
.