E S I
E S I
Excel Semiconductor inc.
AUTOSELECT COMMAND
BYTE / WORD PROGRAM
The autoselect command sequence allows the host
system to access the manufacturer and device
codes, and determine whether or not a sector is
protected, including information about factory-
locked or customer lockable version.
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 5 shows the address and data requirements
for the byte program command sequence. Note that
the autoselect is unavailable while a programming
operation is in progress.
Identifier Code
Manufacturer ID
Device ID
Address
00h
Data
4Ah
01h
DAh(T),
5Bh(B)
Sector Protect Verify
(SA)02h
00 / 01
Table 5 shows the address and data requirements.
This method is an alternative to “A9 high-voltage
method” shown in Table 2, which is intended for
PROM programmers and requires V on address
ID
pin A9. The autoselect command sequence may be
written to an address within sector that is either in
the read mode or erase-suspend-read mode. The
auto-select command may not be written while the
device is actively programming or erasing. The
autoselect command sequence is initiated by first
writing two unlock cycles. This is followed 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 initiating another autoselect com-
mand sequence.
START
Write Program Com-
mand Sequence
Embedded
Program
algorithm in
progress
Data Poll
from System
Once after the device enters the auto-select mode,
the manufacture ID code ( 4Ah ) can be accessed
by one of two ways. Just one read cycle ( with A6,
A1 and A0 = 0 ) can be used. Or four consecutive
read cycles ( with A6 = 1 and A1, A0 = 0 ) for con-
tinuation codes (7Fh) and then another last cycle
for the code (4Ah) (with A6, A1 and A0 = 0) can be
used for reading the manufacturer code.
No
Verify Data
?
Yes
No
Last Address?
Yes
Increment Address
- 4Ah (One-cycle read)
- 7Fh 7Fh 7Fh 7Fh 4Ah (Five-cycle read)
Programming
Completed
The system must write the reset command to return
to the read mode (or erase-suspend-read mode if
the device was previously in Erase Suspend).
Note: See Table 5 for program command sequence
Figure 6. Program Operation
17
Rev. 1D January 5, 2006
ES29LV800D