Document Number: 001-98285 Rev. *R
Page 23 of 108
S29GL01GS/S29GL512S
S29GL256S/S29GL128S
5.4
Command Set
5.4.1
Program Methods
5.4.1.1
Word Programming
Word programming is used to program a single word anywhere in the main Flash Memory Array.
The Word Programming command is a four-write-cycle sequence. 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 Word Program algorithm. The system is not required to provide further controls or timing. The device automatically
generates the program pulses and verifies the programmed cell margin internally. When the Embedded Word Program algorithm is
complete, the EAC then returns to its standby mode.
The system can determine the status of the program operation by using Data Polling Status, reading the Status Register, or
monitoring the RY/BY# output. See
for information on these status bits. See
for information on these status bits. See
for a diagram of the programming operation.
Any commands other than Program Suspend written to the device during the Embedded Program algorithm are ignored. Note that a
hardware reset (RESET# = V
IL
) immediately terminates the programming operation and returns the device to read mode after t
RPH
time. To ensure data integrity, the Program command sequence should be reinitiated once the device has completed the hardware
reset operation.
A modified version of the Word Programming command, without unlock write cycles, is used for programming when entered into the
Lock Register, Password, and PPB ASOs. The same command is used to change volatile bits when entered in to the PPB Lock, and
DYB ASOs. See
for program command sequences.
Figure 5.1
Word Program Operation
START
Write Program Command
Sequence
Data Poll from System
Verify Word?
Last Addresss?
Increment Address
Embedded
Program
algorithm
in progress
Programming Completed
No
No
Yes
Yes
