82802AB Datasheet, PDF (25/53 Pages) Intel Corporation – Firmware Hub (FWH)

Intel^® 82802AB/AC Firmware Hub
R
4.9.1.
T_BLOCK_LK and T_MINUSxx_LK — Block-Locking Registers
Memory Address:
Default Value:
Access:
Size:
FFBx0002h (x = F-0h)
01h
R/W
8 bits (each)
Table 6.
Bit
Function
7:3 Reserved
Read-Lock
2
1 = Prevents read operations in the block where set.
0 = Normal operation for reads in the block where clear. This is the default state.
Lock-Down
1 = Prevents further set or clear operations to the Write Lock and Read Lock bits. Lock-Down only can
1
be set, but not cleared. The block will remain locked-down until reset (with RST# or INIT#), or until
the device is power-cycled.
0 = Normal operation for Write Lock and Read Lock bit altering in the block where clear. This is the
default state.
Write-Lock
0
1 = Prevents program or erase operations in the block where set. This is the default state.
0 = Normal operation for programming and erase in the block where clear.
Register-Based Locking Value Definitions
Data
00h
01h
02h
03h
04h
05h
06h
07h
Reserved
Data 7:3
00000
00000
Read Lock,
Data 2
0
0
00000
0
00000
0
00000
1
00000
1
00000
1
00000
1
Lock-Down,
Data 1
0
0
1
1
0
0
1
1
Write Lock,
Data 0
Resulting block state (1).
0
Full access
1
Write locked. Default state at power-
up
0
Locked open (full access locked down).
1
Write-locked down.
0
Read locked.
1
Read and write locked.
0
Read-locked down.
1
Read- and write-locked down.
Note:
The write-lock bit must be set to the desired protection state prior to starting a program or erase
operation, since it is sampled at the beginning of the operation. Changing the state of the write-lock bit
during a program or erase operation may cause unpredictable results. If the state of the write-lock bit
changes during a program suspend or erase suspend state, changes in the block’s locking status do not
occur immediately. The suspended operation may be resumed successfully. The new lock status will take
place after the program or erase operation completes. The individual bit functions are described in the
following sections.
Datasheet
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