M50FLW040A, M50FLW040B
Status Register
5.3
5.3.1
5.3.2
5.3.3
Erase status (Bit SR5)
This bit indicates if a problem has occurred during the erasing of a Sector or Block. The
Erase Status bit should be read once the Program/Erase Controller Status bit is โ1โ
(Program/Erase Controller inactive).
When the Erase Status bit is โ0โ, the memory has successfully verified that the Sector/Block
has been erased correctly. When the Erase Status bit is โ1โ, the Program/Erase Controller
has applied the maximum number of pulses to the Sector/Block and still failed to verify that
the Sector/Block has been erased correctly.
Once the Erase Status bit is set to โ1โ, it can only be reset to โ0โ by a Clear Status Register
command, or by a hardware reset. If it is set to โ1โ, it should be reset before a new Program
or Erase command is issued, otherwise the new command will appear to have failed, too.
Program status (Bit SR4)
This bit indicates if a problem has occurred during the programming of a byte. The Program
Status bit should be read once the Program/Erase Controller Status bit is โ1โ
(Program/Erase Controller inactive).
When the Program Status bit is โ0โ, the memory has successfully verified that the byte has
been programmed correctly. When the Program Status bit is โ1โ, the Program/Erase
Controller has applied the maximum number of pulses to the byte and still failed to verify
that the byte has been programmed correctly.
Once the Program Status bit is set to โ1โ, it can only be reset to โ0โ by a Clear Status Register
command, or by a hardware reset. If it is set to โ1โ, it should be reset before a new Program
or Erase command is issued, otherwise the new command will appear to have failed, too.
VPP status (Bit SR3)
This bit indicates whether an invalid voltage was detected on the VPP pin at the beginning of
a Program or Erase operation. The VPP pin is only sampled at the beginning of the
operation. Indeterminate results can occur if VPP becomes invalid during a Program or
Erase operation.
Once the VPP Status bit set to โ1โ, it can only be reset to โ0โ by a Clear Status Register
command, or by a hardware reset. If it is set to โ1โ, it should be reset before a new Program
or Erase command is issued, otherwise the new command will appear to have failed, too.
Program Suspend status (Bit SR2)
This bit indicates that a Program operation has been suspended, and that it is waiting to be
resumed. The Program Suspend Status should only be considered valid when the
Program/Erase Controller Status bit is โ1โ (Program/Erase Controller inactive). After a
Program/Erase Suspend command is issued, the memory may still complete the operation
instead of entering the Suspend mode.
When the Program Suspend Status bit is โ0โ, the Program/Erase Controller is active, or has
completed its operation. When the bit is โ1โ, a Program/Erase Suspend command has been
issued and the memory is waiting for a Program/Erase Resume command.
When a Program/Erase Resume command is issued, the Program Suspend Status bit
returns to โ0โ.
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