MC68HC908LJ12 Datasheet, PDF (61/413 Pages) Freescale Semiconductor, Inc – 8-bit microcontroller units

FLASH Memory (FLASH)
Addr.
$FE08
$FE09
Register Name
Read:
FLASH Control Register
(FLCR)
Write:
Reset:
FLASH Block Protect ^Read:
Register Write:
(FLBPR) _Reset:
Bit 7
0
0
BPR7
0
6
5
0
0
0
0
BPR6 BPR5
0
0
= Unimplemented
4
0
0
BPR4
0
3
HVEN
0
BPR3
0
2
1
Bit 0
MASS ERASE PGM
0
0
0
BPR2 BPR1 BPR0
0
0
0
Figure 4-1. FLASH I/O Register Summary
4.3 Functional Description
The FLASH memory consists of an array of 12,288 bytes for user
memory plus a block of 48 bytes for user interrupt vectors. An erased bit
reads as logic 1 and a programmed bit reads as a logic 0. The FLASH
memory page size is defined as 128 bytes, and is the minimum size that
can be erased in a page erase operation. Program and erase operations
are facilitated through control bits in FLASH control register (FLCR). The
address ranges for the FLASH memory are:
• $C000–$EFFF; user memory; 12,288 bytes
• $FFD0–$FFFF; user interrupt vectors; 48 bytes
NOTE:
Programming tools are available from Freescale. Contact your local
Freescale representative for more information.
A security feature prevents viewing of the FLASH contents.¹
Technical Data
62
1. No security feature is absolutely secure. However, Freescale’s strategy is to make reading or
copying the FLASH difficult for unauthorized users.
FLASH Memory (FLASH)
MC68HC908LJ12 — Rev. 2.1
Freescale Semiconductor