XC912BC32CFU8 Motorola Semiconductor Products, XC912BC32CFU8 Datasheet - Page 105

• Manufacturer Part Number: XC912BC32CFU8
• Description: M68HC12B Family Data Sheet
• Manufacturer: Motorola Semiconductor Products

8.1 Introduction
8.2 FLASH EEPROM Array
M68HC12B Family — Rev. 8.0
MOTOROLA
Data Sheet — M68HC12B Family
NOTE:
The 32-Kbyte FLASH EEPROM module for the MC68HC912B32 and
MC68HC912BC32 serves as electrically erasable and programmable, non-volatile
ROM emulation memory. The module can be used for program code that must
either execute at high speed or is frequently executed, such as operating system
kernels and standard subroutines, or it can be used for static data which is read
frequently. The FLASH EEPROM is ideal for program storage for single-chip
applications allowing for field reprogramming.
The MC68HC12BE32 and MC68HC12BC32 does not contain FLASH EEPROM.
The FLASH EEPROM array is arranged in a 16-bit configuration and may be read
as either bytes, aligned words or misaligned words. Access time is one bus cycle
for byte and aligned word access and two bus cycles for misaligned word
operations.
The FLASH EEPROM module requires an external program/erase voltage (V
program or erase the FLASH EEPROM array. The external program/erase voltage
is provided to the FLASH EEPROM module via an external V
damage to the FLASH array, V
–0.35 V. Programming is by byte or aligned word. The FLASH EEPROM module
supports bulk erase only.
The FLASH EEPROM module has hardware interlocks which protect stored data
from accidental corruption. An erase- and program-protected 2-Kbyte block for
boot routines is located at $7800–$7FFF or $F800–$FFFF, depending upon the
mapped location of the FLASH EEPROM array. (The protected boot block on the
initial mask sets, G86W and G75R, is 1-Kbyte and is located at $7C00–$7FFF or
$FC00–$FFFF.)
After reset, the FLASH EEPROM array is located from addresses $8000 to $FFFF
in single-chip mode. In expanded modes, the FLASH EEPROM array is located
from address $0000 to $7FFF; however, it is disabled from the memory map. The
FLASH EEPROM can be mapped to an alternate address range. See
Operating Modes and Resource
FLASH EEPROM
FP
should always be greater than or equal to V
Mapping.
Section 8. FLASH EEPROM
FP
pin. To prevent
Section 5.
Data Sheet
FP
DD
) to
105