Справочник Пользователя для Motorola MC68HC908MR16
FLASH Memory
FLASH Block Protect Register
MC68HC908MR16/MC68HC908MR32 — Rev. 4.0
Advance Information
MOTOROLA
FLASH Memory
65
4.9 FLASH Block Protect Register
The FLASH block protect register (FLBPR) is implemented as a byte
within the FLASH memory, and therefore can be written only during a
programming sequence of the FLASH memory. The value in this register
determines the starting location of the protected range within the FLASH
memory.
within the FLASH memory, and therefore can be written only during a
programming sequence of the FLASH memory. The value in this register
determines the starting location of the protected range within the FLASH
memory.
BPR[7:0] — FLASH Block Protect Bits
These eight bits represent bits [14:7] of a 16-bit memory address.
Bit 15 is logic 1 and bits [6:0] are logic 0s.
Bit 15 is logic 1 and bits [6:0] are logic 0s.
The resultant 16-bit address is used for specifying the start address
of the FLASH memory for block protection. The FLASH is protected
from this start address to the end of FLASH memory at $FFFF. With
this mechanism, the protect start address can be XX00 and XX80
(128 bytes page boundaries) within the FLASH memory.
of the FLASH memory for block protection. The FLASH is protected
from this start address to the end of FLASH memory at $FFFF. With
this mechanism, the protect start address can be XX00 and XX80
(128 bytes page boundaries) within the FLASH memory.
Figure 4-4. FLASH Block Protect Start Address
Refer to
for examples of the protect start address.
Address:
$FF7E
Bit 7
6
5
4
3
2
1
Bit 0
Read:
BPR7
BPR6
BPR5
BPR4
BPR3
BPR2
BPR1
BPR0
Write:
Reset:
0
0
0
0
0
0
0
0
U = Unaffected by reset. Initial value from factory is 1.
Write to this register by a programming sequence to the FLASH memory.
Write to this register by a programming sequence to the FLASH memory.
Figure 4-3. FLASH Block Protect Register (FLBPR)
1
FLBPR VALUE
16-BIT MEMORY ADDRESS
0
0
0
0
0
0
0
START ADDRESS OF FLASH
BLOCK PROTECT