A81L801 Datasheet, PDF (20/47 Pages) AMIC Technology – Stacked Multi-chip Package (MCP) 1 M X 8 Bit / 512K X 16 Bit Boot Sector Flash Memory and 128K x 8 Low Voltage CMOS SRAM

A81L801
section.) The time-out begins from the rising edge of the final
WE pulse in the command sequence.
Once the sector erase operation has begun, only the Erase
Suspend command is valid. All other commands are ignored.
When the Embedded Erase algorithm is complete, the device
returns to reading array data and addresses are no longer
latched. The system can determine the status of the erase
operation by using I/O7, I/O6, or I/O2. Refer to "Write Operation
Status" for information on these status bits.
4 illustrates the algorithm for the erase operation. Refer to the
Erase/Program Operations tables in the "AC Characteristics"
section for parameters, and to the Sector Erase Operations
Timing diagram for timing waveforms.
Erase Suspend/Erase Resume Commands
The Erase Suspend command allows the system to interrupt a
sector erase operation and then read data from, or program
data to, any sector not selected for erasure. This command is
valid only during the sector erase operation, including the 50µs
time-out period during the sector erase command sequence.
The Erase Suspend command is ignored if written during the
chip erase operation or Embedded Program algorithm. Writing
the Erase Suspend command during the Sector Erase time-out
immediately terminates the time-out period and suspends the
erase operation. Addresses are "don't cares" when writing the
Erase Suspend command.
When the Erase Suspend command is written during a sector
erase operation, the device requires a maximum of 20µs to
suspend the erase operation. However, when the Erase
Suspend command is written during the sector erase time-out,
the device immediately terminates the time-out period and
suspends the erase operation.
After the erase operation has been suspended, the system can
read array data from or program data to any sector not
selected for erasure. (The device "erase suspends" all sectors
selected for erasure.) Normal read and write timings and
command definitions apply. Reading at any address within
erase-suspended sectors produces status data on I/O7 - I/O0.
The system can use I/O7, or I/O6 and I/O2 together, to
determine if a sector is actively erasing or is erase-suspended.
See "Write Operation Status" for information on these status
bits.
After an erase-suspended program operation is complete, the
system can once again read array data within non-suspended
sectors. The system can determine the status of the program
operation using the I/O7 or I/O6 status bits, just as in the
standard program operation. See "Write Operation Status" for
more information.
The system may also write the autoselect command sequence
when the device is in the Erase Suspend mode. The device
allows reading autoselect codes even at addresses within
erasing sectors, since the codes are not stored in the memory
array. When the device exits the autoselect mode, the device
reverts to the Erase Suspend mode, and is ready for another
valid operation. See "Autoselect Command Sequence" for
more information.
The system must write the Erase Resume command (address
bits are "don't care") to exit the erase suspend mode and
continue the sector erase operation. Further writes of the
Resume command are ignored. Another Erase Suspend
command can be written after the device has resumed erasing.
START
Write Erase
Command
Sequence
Data Poll
from System
No
Data = FFh ?
Embedded
Erase
algorithm in
progress
Yes
Erasure Completed
Note :
1. See the appropriate Command Definitions table for erase
command sequences.
2. See "I/O3 : Sector Erase Timer" for more information.
Figure 4. Erase Operation
PRELIMINARY (March, 2005, Version 0.0)
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