AM29LV2562M AMD [Advanced Micro Devices], AM29LV2562M Datasheet - Page 36

no-image

AM29LV2562M

Manufacturer Part Number
AM29LV2562M
Description
Manufacturer
AMD [Advanced Micro Devices]
Datasheet
COMMAND DEFINITIONS
Writing specific address and data commands or se-
quences into the command register initiates device op-
erations. Tables
command sequences. Writing incorrect address and
data values or writing them in the improper sequence
may place the device in an unknown state. A reset
command is then required to return the device to read-
ing 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. Refer to the
diagrams.
Reading Array Data
The device is automatically set to reading array data
after device power-up. No commands are required to
retrieve data. The device is ready to read array data
after completing an Embedded Program or Embedded
Erase algorithm.
After the device accepts an Erase Suspend command,
the device enters the erase-suspend-read mode, after
w h i c h t h e s y s t e m c a n r e a d d a t a f r o m a n y
non-erase-suspended sector. After completing a pro-
gramming operation in the Erase Suspend mode, the
system may once again read array data with the same
exception. See the
Commands
The system must issue the reset command to return
the device to the read (or erase-suspend-read) mode if
DQ5 or DQ13 goes high during an active program or
erase operation, or if the device is in the autoselect
mode. See the next section,
more information.
See also
Device Bus Operations
The
rameters, and Figure 13 shows the timing diagram.
Reset Command
Writing the reset command resets the device 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 device to the read
mode. Once erasure begins, however, the device ig-
nores 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 device to
34
Read-Only Operations
Requirements for Reading Array Data
section for more information.
10
AC Characteristics
and
Erase Suspend/Erase Resume
section for more information.
11
table provides the read pa-
define the valid register
Reset
section for timing
Command, for
D A T A S H E E T
in the
Am29LV2562M
the read mode. If the program command sequence is
written while the device is in the Erase Suspend mode,
writing the reset command returns the device to the
erase-suspend-read mode. Once programming be-
gins, 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 the de-
vice entered the autoselect mode while in the Erase
Suspend mode, writing the reset command returns the
device to the erase-suspend-read mode.
If DQ5 or DQ13 goes high during a program or erase
operation, writing the reset command returns the de-
vice to the read mode (or erase-suspend-read mode if
the device was in Erase Suspend).
Note that if DQ1 or DQ9 goes high during a Write
Buffer Programming operation, the system must write
the Write-to-Buffer-Abort Reset command sequence
to reset the device for the next operation.
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.
Table 11 shows the address and data requirements.
This method is an alternative to that shown in Table 3,
which is intended for PROM programmers and re-
quires V
mand sequence may be written to an address that is
either in the read or erase-suspend-read mode. The
autoselect command may not be written while the de-
vice 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 command sequence:
■ A read cycle at address XX00h returns the manu-
■ Three read cycles at addresses 01h, 0Eh, and 0Fh
■ A read cycle to an address containing a sector ad-
The system must write the reset command to return to
the read mode (or erase-suspend-read mode if the de-
vice was previously in Erase Suspend).
facturer code.
return the device code.
dress (SA), and the address 02h on A7–A0 in dou-
bleword mode returns 0101h if the sector is
protected, or 0000h if it is unprotected.
ID
on address pin A9. The autoselect com-
December 16, 2005

Related parts for AM29LV2562M