FlashFlex51 MCU
SST89E564RD / SST89V564RD / SST89E554RC / SST89V554RC
Data Sheet
TABLE
Level
1
2
9-1: S
ECURITY
L
OCK
O
PTIONS
Security Lock Bits
1,2
SFST[7:5]
000
100
SB1
U
P
SB2
1
U
U
SB3
1
U
U
Security Status of:
Block 1
Unlock
SoftLock
Block 0
Unlock
SoftLock
Security Type
No Security Features are Enabled.
MOVC instructions executed from
external program memory are dis-
abled from fetching code bytes from
internal memory, EA# is sampled and
latched on Reset, and further pro-
gramming of the flash is disabled.
Level 2 plus Verify disabled, both
blocks locked.
Level 2 plus Verify disabled. Code in
Block 1 may program Block 0 and vice
versa.
Level 2 plus Verify disabled. Code in
Block 1 may program Block 0.
Same as Level 3 hard lock/hard lock,
but MCU will start code execution
from the internal memory regardless
of EA#.
T9-1.3 1207
3
011
101
010
U
P
U
P
U
P
P
P
U
Hard Lock
SoftLock
Hard Lock
SoftLock
110
001
4
111
P
U
P
P
U
P
U
P
P
Hard Lock
Hard Lock
SoftLock
Hard Lock
1. P = Programmed (Bit logic state = 0), U = Unprogrammed (Bit logic state = 1).
2. SFST[7:5] = Security Lock Status Bits (SB1_i, SB2_i, SB3_i)
9.4 Read Operation Under Lock Condition
The status of security bits SB1, SB2, and SB3 can be read
when the read command is disabled by security lock.
There are three ways to read the status.
1. External host mode: Read-back = 00H (locked)
2. IAP command: Read-back = previous SFDT data
3. MOVC: Read-back = FFH (blank)
©2003 Silicon Storage Technology, Inc.
S71207-04-000
12/03
58
SST [ SILICON STORAGE TECHNOLOGY, INC ]
