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White Electronic Designs Corporation (602) 437-1520 www.whiteedc.com
White Electronic Designs
W78M64VP-XSBX
November 2009
2010 White Electronic Designs Corp. All rights reserved
Rev. 10
White Electronic Designs Corp. reserves the right to change products or specications without notice.
AUTOSELECT
The Autoselect mode provides manufacturer ID, Device
identication, and sector protection information, through
identier codes output from the internal register (separate
from the memory array) on DQ7-DQ0. This mode is primarily
intended for programming equipment to automatically
match a device to be programmed with its corresponding
programming algorithm (see Table 4). The Autoselect codes
can also be accessed in-system.
There are two methods to access autoselect codes. One
uses the autoselect command, the other applies VID on
address pin A9.
When using programming equipment, the autoselect mode
requires VID (11.5 V to 12.5 V) on address pin A9. Address
pins must be as shown in Table 3.
To access Autoselect mode without using high
voltage on A9, the host system must issue the
Autoselect command.
The Autoselect command sequence may be written
to an address within a sector that is either in the read
or erase-suspend-read mode.
The Autoselect command may not be written while
the device is actively programming or erasing.
The system must write the reset command to return
to the read mode (or erase-suspend-read mode if the
sector was previously in Erase Suspend).
It is recommended that A9 apply VID after power-
up sequence is completed. In addition, it is
recommended that A9 apply from VID to VIH/VIL
before power-down the VCC/VIO.
See Table 39 for command sequence details.
When verifying sector protection, the sector address
must appear on the appropriate highest order
address bits (see Table 5 to Table 6). The remaining
address bits are don't care. When all necessary
bits have been set as required, the programming
equipment may then read the corresponding
identier code on DQ15-DQ0. The Autoselect
codes can also be accessed in-system through the
command register.
PROGRAM/ERASE OPERATIONS
These devices are capable of several modes of programming
and or erase operations which are described in detail in the
following sections.
During a write operation, the system must drive CE#
and WE# to VIL and OE# to VIH when providing address,
command, and data. Addresses are latched on the last
falling edge of WE# or CE#, while data is latched on the
1st rising edge of WE# or CE#.
The Unlock Bypass feature allows the host system to send
program commands to the Flash device without rst writing
unlock cycles within the command sequence. See Unlock
Bypass section for details on the Unlock Bypass function.
Note the following:
When the Embedded Program algorithm is complete,
the device returns to the read mode.
The system can determine the status of the program
operation by reading the DQ status bits. Refer to
the Write Operation Status for information on these
status bits.
An “0” cannot be programmed back to a “1.” A
succeeding read shows that the data is still “0.”
Only erase operations can convert a “0” to a “1.”
Any commands written to the device during the
Embedded Program/Erase are ignored except the
Suspend commands.
Secured Silicon Sector, Autoselect, and CFI
functions are unavailable when a program operation
is in progress.
A hardware reset and/or power removal immediately
terminates the Program/Erase operation and the
Program/Erase command sequence should be
reinitiated once the device has returned to the read
mode to ensure data integrity.
Programming is allowed in any sequence and across
sector boundaries for single word programming
operation. See Write Buffer Programming when
using the write buffer.
Programming to the same word address multiple
times without intervening erases is permitted.