
MC68HC05X4 Rev 1.0
MOTOROLA
Resets, Interrupts and Low Power Modes
For More Information On This Product,
Go to: www.freescale.com
47
Resets, Interrupts and Low Power Modes
General Description
Contents
Resets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Power-on reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
RESET pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Illegal address reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Computer operating properly (COP) reset . . . . . . . . . . . . . . . . . . .49
Resets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Non-maskable software interrupt (SWI) . . . . . . . . . . . . . . . . . . . . .50
Maskable hardware interrupts. . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
MCAN interrupt (CIRQ). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Hardware controlled interrupt sequence. . . . . . . . . . . . . . . . . . . . .52
Low power modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
STOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
WAIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
Data retention mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Resets
The MCU can be reset in four ways: by the initial power-on reset
function, by an active low input to the RESET pin, by an opcode fetch
from an illegal address, and by a COP watchdog timer reset. See
Figure 1
, below.
1-resets
F
Freescale Semiconductor, Inc.
n
.