MC908AS60ACFU Datasheet, PDF (53/414 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

FLASH-1 Control and Block Protect Registers
4.3.2 FLASH-1 Block Protect Register
The FLASH-1 Block Protect Register (FL1BPR) is implemented as a byte within the FLASH-1 memory
and therefore can only be written during a FLASH programming sequence. The value in this register
determines the starting location of the protected range within the FLASH-1 memory.
Address: $FF80
Read:
Write:
Bit 7
BPR7
6
BPR6
5
BPR5
4
BPR4
3
BPR3
2
BPR2
1
BPR1
Bit 0
BPR0
Figure 4-2. FLASH-1 Block Protect Register (FL1BPR)
FL1BPR[7:0] — Block Protect Register Bit 7 to Bit 0
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.
The resultant 16-bit address is used for specifying the start address of the FLASH-1 memory for block
protection. FLASH-1 is protected from this start address to the end of FLASH-1 memory at $FFFF.
With this mechanism, the protect start address can be $XX00 and $XX80 (128 byte page boundaries)
within the FLASH-1 array.
16-bit memory address
Start address of FLASH block protect 1
FLBPR value
0000000
Figure 4-3. FLASH-1 Block Protect Start Address
FLASH-1 Protected Ranges
FL1BPR[7:0]
$FF
$FE
$FD
Protected Range
No Protection
$FF00 – $FFFF
$FE80 – $FFFF
$0B
$8580 – $FFFF
$0A
$8500 – $FFFF
$09
$8480 – $FFFF
$08
$8400 – $FFFF
$04
$8200 – $FFFF
$03
$8180 – $FFFF
$02
$8100 – $FFFF
$01
$8080 – $FFFF
$00
$8000 – $FFFF
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
Freescale Semiconductor
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