7 sle bit, 8 rdy/bsy bit – Rainbow Electronics AT25DF081A User Manual
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8715C–SFLSH–11/2012
AT25DF081A
11.1.7 SLE Bit
The SLE bit is used to enable and disable the Sector Lockdown and Freeze Sector Lockdown State commands.
When the SLE bit is in the logical “0” state (the default state after power-up), the Sector Lockdown and Freeze Sec-
tor Lockdown commands are disabled. If the Sector Lockdown and Freeze Sector Lockdown commands are
disabled, then any attempts to issue the commands will be ignored. This provides a safeguard for these commands
against accidental or erroneous execution. When the SLE bit is in the logical “1” state, the Sector Lockdown and
Freeze Sector Lockdown State commands are enabled.
Unlike the WEL bit, the SLE bit does not automatically reset after certain device operations. Therefore, once set,
the SLE bit will remain in the logical “1” state until it is modified using the Write Status Register Byte 2 command or
until the device has been power cycled. The Reset command has no effect on the SLE bit.
If the Freeze Sector Lockdown State command has been issued, then the SLE bit will be permanently reset in the
logical “0” state to indicate that the Sector Lockdown command has been disabled.
11.1.8 RDY/BSY Bit
The RDY/BSY bit is used to determine whether or not an internal operation, such as a program or erase, is in prog-
ress. To poll the RDY/BSY bit to detect the completion of a program or erase cycle, new Status Register data must
be continually clocked out of the device until the state of the RDY/BSY bit changes from a logical “1” to a logical “0”.
Figure 11-1. Read Status Register
SCK
CS
SI
SO
MSB
2
3
1
0
0
0
0
0
0
1
0
1
6
7
5
4
10 11
9
8
12
21 22
17
20
19
18
15 16
13 14
23 24
28 29
27
26
25
30
OPCODE
MSB
MSB
D
D
D
D
D
D
D
D
D
D
MSB
D
D
D
D
D
D
D
D
D
D
D
D
D
D
STATUS REGISTER
BYTE 1
STATUS REGISTER
BYTE 1
STATUS REGISTER
BYTE 2
HIGH-IMPEDANCE