Rainbow Electronics AT25DF081A - Manual (Page 32)

32
8715C–SFLSH–11/2012
AT25DF081A
Notes: 1. Only bits 4 and 3 of Status Register Byte 2 will be modified when using the Write Status Register Byte 2 command.
2. R/W = Readable and writeable
R = Readable only
11.1.1 SPRL Bit
The SPRL bit is used to control whether the Sector Protection Registers can be modified or not. When the SPRL
bit is in the logical “1” state, all Sector Protection Registers are locked and cannot be modified with the Protect Sec-
tor and Unprotect Sector commands (the device will ignore these commands). In addition, the Global Protect and
Global Unprotect features cannot be performed. Any sectors that are presently protected will remain protected, and
any sectors that are presently unprotected will remain unprotected.
When the SPRL bit is in the logical “0” state, all Sector Protection Registers are unlocked and can be modified (the
Protect Sector and Unprotect Sector commands, as well as the Global Protect and Global Unprotect features, will
be processed as normal). The SPRL bit defaults to the logical “0” state after device power-up. The Reset command
has no effect on the SPRL bit.
The SPRL bit can be modified freely whenever the WP pin is deasserted. However, if the WP pin is asserted, then
the SPRL bit may only be changed from a logical “0” (Sector Protection Registers are unlocked) to a logical “1”
(Sector Protection Registers are locked). In order to reset the SPRL bit back to a logical “0” using the Write Status
Register Byte 1 command, the WP pin will have to first be deasserted.
The SPRL bit is the only bit of Status Register Byte 1 that can be user modified via the Write Status Register Byte
1 command.
11.1.2 EPE Bit
The EPE bit indicates whether the last erase or program operation completed successfully or not. If at least one
byte during the erase or program operation did not erase or program properly, then the EPE bit will be set to the
logical “1” state. The EPE bit will not be set if an erase or program operation aborts for any reason such as an
attempt to erase or program a protected region or a locked down sector or if the WEL bit is not set prior to an erase
or program operation. The EPE bit will be updated after every erase and program operation.
Table 11-2. Status Register Format – Byte 2
Bit (1) Name Type (2) Description
7 RES Reserved for future use R 0 Reserved for future use
6 RES Reserved for future use R 0 Reserved for future use
5 RES Reserved for future use R 0 Reserved for future use
4 RSTE Reset Enabled R/W
0 Reset command is disabled (default)
1 Reset command is enabled
3 SLE Sector Lockdown Enabled R/W
0
Sector Lockdown and Freeze Sector Lockdown State
commands are disabled (default)
1
Sector Lockdown and Freeze Sector Lockdown State
commands are enabled
2 RES Reserved for future use R 0 Reserved for future use
1 RES Reserved for future use R 0 Reserved for future use
0 RDY/BSY Ready/Busy Status R
0 Device is ready
1 Device is busy with an internal operation