mc68hc908lj24 Freescale Semiconductor, Inc, mc68hc908lj24 Datasheet - Page 170

• Manufacturer Part Number: mc68hc908lj24
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Monitor ROM (MON)
Data Sheet
170
NOTE:
In monitor mode, the MCU uses different vectors for reset, SWI
(software interrupt), and break interrupt than those for user mode. The
alternate vectors are in the $FE page instead of the $FF page and allow
code execution from the internal monitor firmware instead of user code.
Exiting monitor mode after it has been initiated by having a blank reset
vector requires a power-on reset (POR). Pulling RST low will not exit
monitor mode in this situation.
Table 10-2
mode vectors.
Monitor
Modes
User
Figure 10-2. Low-Voltage Monitor Mode Entry Flowchart
summarizes the differences between user mode and monitor
Table 10-2. Mode Differences (Vectors)
Monitor ROM (MON)
Vector
$FFFE
$FEFE
Reset
High
MONITOR MODE
TRIGGERED?
POR RESET
IS VECTOR
EXECUTE
MONITOR
BLANK?
CODE
Vector
$FEFF
$FFFF
Reset
POR
Low
YES
YES
NO
$FEFC
Vector
$FFFC
NO
Break
High
Functions
MC68HC908LJ24/LK24 — Rev. 2.1
NORMAL USER
Vector
$FFFD
$FEFD
Break
Low
MODE
Freescale Semiconductor
Vector
$FFFC
$FEFC
High
SWI
Vector
$FFFD
$FEFD
Low
SWI