A82DL16X4T Datasheet, PDF (23/57 Pages) AMIC Technology – Stacked Multi-Chip Package (MCP) Flash Memory and SRAM, A82DL16x4T(U) 16 Megabit (2Mx8 Bit/1Simultaneous Operation Flash Memory and 4M (256Kx16 Bit) S

A82DL16x4T(U) Series
COMMAND DEFINITIONS
Writing specific address and data commands or sequences
into the command register initiates device operations. Table
12 defines the valid register 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 reading array data.
All addresses are latched on the falling edge of WE or
CE_F , whichever happens later. All data is latched on the
rising edge of WE or CE_F , whichever happens first. Refer
to the AC Characteristics section for timing 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 also 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-suspend-read mode,
after which the system can read data from any non-erase-
suspended sector within the same bank. After completing a
programming operation in the Erase Suspend mode, the
system may once again read array data with the same
exception. See the Erase Suspend/Erase Resume
Commands section for more information.
The system must issue the reset command to return a bank
to the read (or erase-suspend-read) mode if I/O5 goes high
during an active program or erase operation, or if the bank is
in the autoselect mode. See the next section, Reset
Command, for more information.
See also Requirements for Reading Array Data in the Device
Bus Operations section for more information. The Read-Only
Operations table provides the read parameters, and Figure
11 shows the timing 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 sequence
cycles in an erase command sequence before erasing
begins. This resets the bank to which the system was writing
to reading array data. 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 bank to which the
system was writing to reading array data. 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-suspend-read mode. Once programming begins,
however, the device ignores reset commands until the
operation is complete.
The reset command may be written between the sequence
cycles in an autoselect command sequence. Once in the
autoselect mode, the reset command must be written to
return to reading array data. If a bank entered the autoselect
mode while in the Erase Suspend mode, writing the reset
command returns that bank to the erase-suspend-read mode.
If I/O5 goes high during a program or erase operation, writing
the reset command returns the banks to reading array data
(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. Table 12 shows the
address and data requirements. This method is an
alternative to that shown in Table 5, which is intended for
PROM programmers and requires VID on address pin A9.
The autoselect command sequence may be written to an
address wit h in a bank that is either in t he read or erase-
suspend-read mode. The autoselect command may not be
written while the device is actively programming 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 autoselect command. T he
bank then enter s the autoselect mode. The system may read
at any address within the same bank any number of times
without initiating another autoselect command sequence:
A read cycle at address (BA)XX00h (where BA is the bank
address) returns the manufacturer code.
A read cycle at address (BA)XX01h in word mode (or
(BA)XX02h in byte mode) returns the device code.
A read cycle to an address containing a sector address
(SA) within the same bank, and the address 02h on A7-A0
in word mode (or the address 04h on A6-A-1 in byte mode)
returns 01h if the sector is protected, or 00h if it is
unprotected. (Refer to Tables 3-4 for valid sector
addresses).
The system must write the reset command to return to
reading array data (or erase-suspend-read mode if the bank
was previously in Erase Suspend).
Byte/Word Program Command Sequence
The system may program the device by word or byte,
depending on the state of the BYTE_F 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 automatically provides
internally generated program pulses and verifies the
programmed cell margin. Table 12 shows the address and
data requirements for the byte program command sequence.
When the Embedded Program algorithm is complete, that
bank then returns to reading array data and addresses are
no longer latched. The system can determine the status of
the program operation by using I/O7, I/O6, or RY/BY . Refer
to the Write Operation Status section for information on these
status bits.
Any commands written to the device during the Embedded
Program Algorithm are ignored. Note that a hardware reset
immediately terminates the program operation. The program
command sequence should be reinitiated once that bank has
returned to reading array data, to ensure data integrity.
Programming is allowed in any sequence and across sector
boundaries. A bit cannot be programmed from “0” back to a
“1.” Attempting to do so may cause that bank to set I/O5 = 1,
or cause the I/O7 and I/O6 status bits to indicate the operation
was successful. However, a succeeding read will show that
the data is still “0.” Only erase operations can convert a “0” to
a “1.”
PRELIMINARY (August, 2005, Version 0.0)
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AMIC Technology, Corp.