n25q256 Numonyx, n25q256 Datasheet - Page 49

• Manufacturer Part Number: n25q256
• Description: 256-mbit 3 V, Multiple I/o, 4-kbyte Subsector Erase, Xip Enabled, Serial Flash Memory With 108 Mhz Spi Bus Interface
• Manufacturer: Numonyx

N25Q256 - 3 V
6.5.1
6.5.2
6.5.3
6.5.4
P/E Controller Status bit
The bit 7 of the Flag Status register represents the Program/Erase Controller Status bit, It
indicates whether there is a Program/Erase internal cycle active. When P/E Controller
Status bit is Low (FSR<7>=0) the device is busy; when the bit is High (FSR<7>=1) the
device is ready to process a new command.
This bit has the same meaning of Write In Progress (WIP) bit of the standard SPI Status
Register, but with opposite logic: FSR<7> = not WIP
It's possible to make the polling instructions, to check if the internal modify operations are
finished, both on the Flag Status register bit 7 or on WIP bit of the Status Register.
Erase Suspend Status bit
The bit 6 of the Flag Status register represents the Erase Suspend Status bit, It indicates
that an Erase operation has been suspended or is going to be suspended.
The bit is set (FSR<6>=1) within the Erase Suspend Latency time, that is as soon as the
Program/Erase Suspend command (PES) has been issued, therefore the device may still
complete the operation before entering the Suspend Mode.
The Erase Suspend Status should be considered valid when the P/E Controller bit is high
(FSR<7>=1).
When a Program/Erase Resume command (PER) is issued the Erase Suspend Status bit
returns Low (FSR<6>=0)
Erase Status bit
The bit 5 of the Flag Status Register represents the Erase Status bit. It indicates an erase
failure or a protection error when an erase operation is issued.
When the Erase Status bit is High (FSR<5>=1) after an Erase failure that means that the
P/E Controller has applied the maximum pulses number to the portion to be erased and still
failed to verify that it has correctly erased.
The Erase Status bit should be read once the P/E Controller Status bit is High.
The Erase Status bit is related to all possible erase operations: Sector Erase, Sub Sector
Erase, and Bulk Erase in all the three available protocols (SPI, DIO-SPI and QIO-SPI).
Once the bit 5 is set High, it can only be reset Low (FSR<5>=0) by a Clear Flag Status
Register command (CLFSR).
If set High it should be reset before a new Erase command is issued; otherwise the new
command will appear to fail.
Program Status bit
The bit 4 of the Flag Status Register represents the Program Status bit. It indicates:
a Program failure
an attempt to program a '1' on '0' when VPP=VPPH (only when the pattern is a multiple
of 64 bits, otherwise this bit is "Don't care").
a protection error when a program is issued
Micron Technology, Inc., reserves the right to change products or specifications without notice.
Volatile and Non Volatile Registers
©2010 Micron Technology, Inc. All rights reserved.
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