Datasheet

FLASH-1 Memory (FLASH-1)
MC68HC908GR60A • MC68HC908GR48A • MC68HC908GR32A Data Sheet, Rev. 5
Freescale Semiconductor 43
2.6.2.2 FLASH-1 Block Protect Register
The FLASH-1 block protect register (FL1BPR) is implemented as a byte within the FLASH-1 memory;
therefore, it 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.
FL1BPR[7:0] — Block Protect Register Bits 7 to 0
These eight bits represent bits [14:7] of a 16-bit memory address. Bit 15 is a 1 and bits [6:0] are 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.
Figure 2-5. FLASH-1 Block Protect Start Address
Address: $FF80
Bit 7654321Bit 0
Read:
BPR7 BPR6 BPR5 BPR4 BPR3 BPR2 BPR1 BPR0
Write:
Unaffected by reset
Figure 2-4. FLASH-1 Block Protect Register (FL1BPR)
Table 2-2. FLASH-1 Protected Ranges
FL1BPR[7:0] Protected Range
$FF No protection
$FE $FF00–$FFFF
$FD
↓
$0B
$FE80–$FFFF
↓
$8580–$FFFF
$0A $8500–$FFFF
$09 $8480–$FFFF
$08
↓
$04
$8400–$FFFF
↓
$8200–$FFFF
$03 $8180–$FFFF
$02 $8100–$FFFF
$01 $8080–$FFFF
$00 $8000–$FFFF
1
FLBPR VALUE
16-BIT MEMORY ADDRESS
0000000
START ADDRESS OF FLASH
BLOCK PROTECT