mc68hc908lb8 Freescale Semiconductor, Inc, mc68hc908lb8 Datasheet - Page 55

• Manufacturer Part Number: mc68hc908lb8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

4.5 Low Power Modes
4.5.1 Wait Mode
The WAIT instruction places the MCU in a low power consumption mode. While in WAIT the op
amp/comparator cannot be enabled or disabled. If the op amp/comparator module is not needed during
wait mode, reduce power consumption by disabling the op amp/comparator before executing the WAIT
command.
4.5.2 Stop Mode
The op amp/comparator is inactive after execution of the STOP command. The
op amp/comparator will be in a low-power state and will not drive its output pin. When the MCU exits stop
mode after and external interrupt, the op amp/comparator continues operation.
4.6 Op Amp/Comparator Control Register
There is a single operational control register (OACCR) that contains the enable bit for the op
amp/comparator.
OACM — Op Amp/Comparator Mode Select Bit
Freescale Semiconductor
This bit selects between 2 modes of operation, op amp mode and comparator mode.
1 = Op amp mode selected
Address: $0039
In order to read the digital states of the pins configured as inputs, the data
direction register bit must be a 0; to read the states of the pins configured
as outputs the data direction register bit must be a 1.
Reset:
Read:
Write:
GROUND
GROUND
Figure 4-3. Op Amp/Comparator Control Register (OACCR)
V+
V–
OACM
Bit 7
0
Figure 4-2. Op Amp/Comparator Block Diagram
= Unimplemented
U
6
OACE
OACE
MC68HC908LB8 Data Sheet, Rev. 1
U
5
U
4
U = Unaffected
+
-
OACE
U
3
U
2
OACE
U
1
V
FLOATING
OUT
OACE
Bit 0
0
Low Power Modes
55