E S I
E S I
ADVANCED INFORMATION
Excel Semiconductor inc.
BYTE / WORD PROGRAM
Program Status Bits : DQ7, DQ6 or RY/BY#
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 auto-
matically provides internally generated program
pulses and verifies the programmed cell margin.
Table 9 shows the address and data requirements
for the byte program command sequence. Note that
the autoselect, commands related with the security
sector, and CFI modes are unavailable while a pro-
gramming operation is in progress.
When the Embedded Program algorithm is com-
plete, 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 the Write
Operation Status section Table 10 for information on
these status bits.
Any Commands Ignored during Program-
ming Operation
Any commands written to the device during the
Embedded Program algorithm are ignored. Note that
a hardware reset can 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.
Programming from “0” back to “1”
Programming is allowed in any sequence and
across sector boundaries. But a bit cannot be pro-
grammed 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”.
START
Write Program Com-
mand Sequence
Embedded
Program
Data Poll
from System
Unlock Bypass
algorithm in
progress
In the ES29DL320 device, an unlock bypass pro-
gram mode is provided for faster programming oper-
ation. In this mode, two cycles of program command
sequences can be saved. To enter this mode, an
unlock bypass enter command should be first written
to the system. The unlock bypass enter command
sequence is initiated by first writing two unlock
cycles. This is followed by a third write cycle contain-
ing the unlock bypass command, 20h. That bank
then enters the unlock-bypass program mode. A
two-cycle unlock bypass program command
sequence is all that is required to program in this
mode. The first cycle in this sequence contains the
unlock bypass program set-up command, A0h; the
second cycle contains the program address and
data. Additional data is programmed in the same
manner. This mode dispenses with the initial two
unlock cycles required in the standard program com-
mand sequence, resulting in faster total program-
ming time. Table 9 shows the requirements for the
command sequence.
No
Verify Data
?
Yes
No
Last Address?
Yes
Increment Address
Programming
Completed
Note: See Table 9 for program command sequence
Figure 8. Program Operation
25
Rev. 0E May 25, 2006
ES29DL320
EXCELSEMI [ EXCEL SEMICONDUCTOR INC. ]
