AM29PDL128G Datasheet, PDF (36/71 Pages) SPANSION – 128 Megabit (8 M x 16-Bit/4 M x 32-Bit) CMOS 3.0 Volt-only, Simultaneous Read/ Write Flash Memory with VersatileIO Control

PRELIMINARY
COMMAND DEFINITIONS
Writing specific address and data commands or se-
quences into the command register initiates device op-
erations. Tables 14, 15, 16, and 17 define the valid
register command sequences. Writing incorrect ad-
dress and data values or writing them in the im-
proper sequence may place the device in an
unknown state. A reset command is then required to
return the device to reading array data.
All addresses are latched on the falling edge of WE#
or CE#, whichever happens later. All data is latched on
the rising edge of WE# or CE#, whichever happens
first. See “AC Characteristics” on page 53 for timing di-
agrams.
Reading Array Data
The device is automatically set to reading array data
after device power-up. No commands are required to
retrieve data. Each bank is ready to read array data
after completing an Embedded Program or Embedded
Erase algorithm.
After the device accepts an Erase Suspend command,
the corresponding bank enters the erase-sus-
pend-read mode, after which the system can read
data from any non-erase-suspended sector within the
same bank. The system can read array data using the
standard read timing, except that if it reads at an ad-
dress within erase-suspended sectors, the device out-
puts status data. After completing a programming
operation in the Erase Suspend mode, the system
may once again read array data with the same excep-
tion. See “Erase Suspend/Erase Resume Commands”
on page 38 for more information.
The system must issue the reset command to return a
bank to the read (or erase-suspend-read) mode if DQ5
goes high during an active program or erase opera-
tion, or if the bank is in the autoselect mode. See the
next section, Reset Command, for more information.
See also See “Requirements for Reading Array Data”
on page 11 in the Device Bus Operations section for
more information. See “Read-Only Operations” table
for the read parameters, and Figure 12 shows the tim-
ing diagram.
Reset Command
Writing the reset command resets the banks to the
read or erase-suspend-read mode. Address bits are
don’t cares for this command.
The reset command may be written between the se-
quence cycles in an erase command sequence before
erasing begins. This resets the bank to which the sys-
tem was writing to the read mode. Once erasure be-
gins, however, the device ignores reset commands
until the operation is complete.
The reset command may be written between the
sequence cycles in a program command sequence
before programming begins. This resets the bank to
which the system was writing to the read mode. If the
program command sequence is written to a bank that
is in the Erase Suspend mode, writing the reset
command returns that bank to the erase-sus-
pend-read mode. Once programming begins, however,
the device ignores reset commands until the operation
is complete.
The reset command may be written between the se-
quence cycles in an autoselect command sequence.
Once in the autoselect mode, the reset command
must be written to return to the read mode. If a bank
entered the autoselect mode while in the Erase Sus-
pend mode, writing the reset command returns that
bank to the erase-suspend-read mode.
If DQ5 goes high during a program or erase operation,
writing the reset command returns the banks to the
read mode (or erase-suspend-read mode if that bank
was in Erase Suspend).
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
cannot be written while the device is actively program-
ming or erasing in the other 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 au-
toselect command. The bank then enters the autose-
lect mode. The system may read any number of
autoselect codes without reinitiating the command se-
quence.
Table 14 and Table 16 show the address and data re-
quirements. To determine sector protection informa-
tion, the system must write to the appropriate bank
address (BA) and sector address (SA). Table 5 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).
Enter SecSi Sector/Exit SecSi Sector
Command Sequence
The SecSi Sector region provides a secured data area
containing a random, eight word/four double word
electronic serial number (ESN). The system can ac-
October 28, 2004
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