PF38F5070M0Y0T0 NUMONYX [Numonyx B.V], PF38F5070M0Y0T0 Datasheet - Page 62

• Manufacturer Part Number: PF38F5070M0Y0T0
• Description: Numonyx StrataFlash Wireless Memory
• Manufacturer: NUMONYX [Numonyx B.V]

14.0
14.1
14.2
Figure 22: Operating Mode with Correct Command Sequence Example
Datasheet
62
Address/Data [A/D]
WE# [W]
OE# [G]
ADV#
CE#
Dual-Operation Considerations
The multi-partition architecture of the device allows background programming (or
erasing) to occur in one partition while data reads (or code execution) take place in
another partition.
Memory Partitioning
The flash memory array is divided into multiple 8-Mbit partitions, which allows
simultaneous read-while-write operations. Simultaneous program and erase is not
allowed. Only one partition at a time can be in program or erase mode.
The flash device supports read-while-write operations with bus cycle granularity and
not command granularity. In other words, it is not assumed that both bus cycles of a
two cycle command (an erase command for example) will always occur as back to back
bus cycles to the flash device. In practice, code fetches (reads) may be interspersed
between write cycles to the flash device, and they will likely be directed to a different
partition than the one being written. This is especially true when a processor is
executing code from one partition that instructs the processor to program or erase in
another partition.
Read-While-Write Command Sequences
When issuing commands to the device, a read operation can occur between 2-cycle
Write command’s
between a 2-cycle commands write sequence causes a command sequence error. (See
Figure
When reading from the same partition after issuing a Setup command, Status Register
data is returned, regardless of the read mode of the partition prior to issuing the Setup
command.
Partition A
24)
Data: 0x20
(Figure
22, and
Partition A
Figure
Numonyx™ StrataFlash
23). However, a write operation issued
Data: 0xD0
®
Wireless Memory (L18 AD-Mux)
Partition B
Order Number: 313295-04
Data: 0xFF
November 2007