M28W640 STMicroelectronics, M28W640 Datasheet - Page 20

• Manufacturer Part Number: M28W640
• Description: 64 Mbit 4Mb x16/ Boot Block 3V Supply Flash Memory
• Manufacturer: STMicroelectronics

M28W640CT, M28W640CB
gram/Erase Controller Status bit is High (Program/
Erase Controller inactive). Bit 2 is set within 5µs of
the Program/Erase Suspend command being is-
sued therefore the memory may still complete the
operation rather than entering the Suspend mode.
When a Program/Erase Resume command is is-
sued the Program Suspend Status bit returns Low.
Block Protection Status (Bit 1). The Block Pro-
tection Status bit can be used to identify if a Pro-
gram or Erase operation has tried to modify the
contents of a locked block.
Table 10. Status Register Bits
Note: Logic level '1' is High, '0' is Low.
20/54
Bit
7
6
5
4
3
2
1
0
P/E.C. Status
Erase Suspend Status
Erase Status
Program Status
V
Program Suspend Status
Block Protection Status
Reserved
PP
Status
Name
Logic Level
'1'
'0'
'1'
'0'
'1'
'0'
'1'
'0'
'1'
'0'
'1'
'0'
'1'
'0'
When the Block Protection Status bit is High (set
to ‘1’), a Program or Erase operation has been at-
tempted on a locked block.
Once set High, the Block Protection Status bit can
only be reset Low by a Clear Status Register com-
mand or a hardware reset. If set High it should be
reset before a new command is issued, otherwise
the
Reserved (Bit 0). Bit 0 of the Status Register is
reserved. Its value must be masked.
Note: Refer to Appendix C, Flowcharts and
Pseudo Codes, for using the Status Register.
new
Ready
Busy
Suspended
In progress or Completed
Erase Error
Erase Success
Program Error
Program Success
V
V
Suspended
In Progress or Completed
Program/Erase on protected Block, Abort
No operation to protected blocks
PP
PP
command
Invalid, Abort
OK
Definition
will
appear
to
fail.