W19B160BT Datasheet, PDF (12/48 Pages) Winbond – 16Mbit, 2.7~3.6 volt CMOS flash memory

W19B160BT/B DATA SHEET
6.2 COMMAND DEFINITIONS
The device operation can be initiated by writing specific address and data commands or sequences
into the command register. The device will be reset to reading array data when writing incorrect
address and data values or writing them in the improper sequence.
The addresses will be latched on the falling edge of #WE or #CE, whichever happens later; while the
data will be latched on the rising edge of #WE or #CE, whichever happens first. Please refer to timing
waveforms.
6.2.1 Reading Array Data
After device power-up, it is automatically set to reading array data. There is no commands are
required to retrieve data. After completing an Embedded Program or Embedded Erase algorithm, the
device is ready to read array data.
The system must initiate the reset command to return the device to read mode if DQ5 goes high
during an active program or erase operation; otherwise, the device is in the auto select mode. See
Reset Command section and Requirements for Reading Array Data in the Device Bus Operations
section for more information.
6.2.2 Reset Command
The device will be to the read when writing the reset command. For this command, the address bits
are Don’t Care.
The reset command may be written between the sequence cycles in an erase command sequence
before erasing begins. This resets the device to which the system was writing to the read mode. Once
erasure begins, 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 device, to which the system was writing to the read mode.
The reset command may be written between the sequence cycles in an auto select command
sequence. When in the auto select mode, the reset command must be written to return to the read
mode. If DQ5 goes high during a program or erase operation, writing the reset command returns the
device to the read mode.
6.2.3 Auto-select Command Sequence
The auto select command sequence provides the host system to access the manufacturer and device
codes, and determine whether a sector is protected or not. This is an alternative method, which is
intended for PROM programmers and requires V_ID on address pin A9. The auto select command
sequence may be written to an address within the device that is in the read mode. When the device is
actively programming or erasing, the auto select command may not be written.
The first writing two unlock cycles initiate the auto select command sequence. This is followed by a
third write cycle that contains the auto select command. The device then enters into the auto select
mode. The system may read at any address without initiating another auto select command sequence:
• A read cycle at address XX00h returns the manufacturer code.
• A read cycle at address XX01h in word mode (or XX02h in byte mode) returns the device code.
• A read cycle to an address containing a sector address (SA), and the address 02h on A7-A0 in
word mode (or the address 04h in byte mode) returns 01h if the sector is protected, or 00h if it is
unprotected.
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