Comparator Control Register (Cmr0C) - Fujitsu 8FX Hardware Manual

MB95630H Series
28.6.1

Comparator Control Register (CMR0C)

The comparator control register (CMR0C) has the following functions:
• To power up or power down the comparator (CMR0C:PD)
• To enable or disable comparator output (CMR0C:VCOE)
• To enable and disable comparator analog input (CMR0C:VCID)
Except in stop mode, watch mode or time-base timer mode, if CMR0C:IE has
been set to "1", upon detection of a rising edge or falling edge of comparator
output, the comparator generates an interrupt request and the interrupt flag bit
(CMR0C:IF) is automatically set to "1" at the same time.
The output status of the comparator can be read through the OS bit in the
comparator control register (CMR0C).
■ Register Configuration
bit 7
Field —
Attribute —
Initial value 0
■ Register Functions
[bit7:6] Undefined bits
Their read values are always "0". Writing values to these bits has no effect on operation.
[bit5] OS: Output status bit
This bit indicates the output status of the comparator.
bit5
Reading "0"
Reading "1"
Note: This bit is not updated in stop mode, watch mode or time-base timer mode. When the PD bit is set to
"1" (to power down the comparator), the OS bit becomes "0".
[bit4] IF: Output edge detection interrupt flag bit
This bit detects the output rising edge and the output falling edge of the comparator.
With the comparator in operation, this bit is set to "1" if an output rising edge or an output falling edge
occurs.
When read by the read-modify-write (RMW) type of instruction, this bit always returns "1".
bit4
Reading "0"
Reading "1"
Writing "0"
Writing "1"
Note: This bit is not updated in stop mode, watch mode or time-base timer mode.
MN702-00009-2v0-E
6 5
— OS
— R
0 0
Indicates that the comparator outputs "L".
Indicates that the comparator outputs "H".
Indicates that no output rising edge/falling edge has occurred.
Indicates that an output rising edge/falling edge has occurred.
Clears this bit.
Has no effect on operation.
FUJITSU SEMICONDUCTOR LIMITED
4 3
IF IE
R/W R/W
0 0
Details
Details
CHAPTER 28 COMPARATOR
28.6 Register
2 1
VCID VCOE
R/W R/W
1 0
0
PD
R/W
1
601