ADSP-BF50x Blackfin Processor Hardware Reference
6-39
Internal Flash Memory
Reading a Block’s Lock Status
The lock status of every block can be read in the read electronic signature
mode of the device. To enter this mode write 0x90 to the device. Subse-
quent reads at the address specified in
Table 6-6 on page 6-17
output the
protection status of that block. The lock status is represented by
D0
and
D1
.
D0
indicates the block lock/unlock status and is set by the lock com-
mand and cleared by the unlock command. It is also automatically set
when entering lock-down.
D1
indicates the lock-down status and is set by
the lock-down command. It cannot be cleared by software, only by a hard-
ware reset or power-down.
The following sections explain the operation of the locking system.
Locked State
The default status of all blocks on power-up or after a hardware reset is
locked (states (0,0,1) or (1,0,1)). Locked blocks are fully protected from
any program or erase. Any program or erase operations attempted on a
locked block returns an error in the status register. The status of a locked
block can be changed to unlocked or lock-down using the appropriate
software commands. An unlocked block can be locked by issuing the lock
command.
Unlocked State
Unlocked blocks (states (0,0,0), (1,0,0) (1,1,0)), can be programmed or
erased. All unlocked blocks return to the locked state after a hardware
reset or when the device is powered-down. The status of an unlocked
block can be changed to locked or locked-down using the appropriate
software commands. A locked block can be unlocked by issuing the
unlock command.
Summary of Contents for EZ-KIT Lite ADSP-BF506F
Page 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Page 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...