11.2 Register Descriptions
11.2.1 PWM Control Register (PWCR)
PWCR is an 8-bit write-only register for input clock selection.
Upon reset, PWCR is initialized to H'FC.
Bits 7 to 2: Reserved bits
Bits 7 to 2 are reserved; they are always read as 1, and cannot be modified.
Bits 1 and 0: Clock select 1 and 0 (PWCR1, PWCR0)
Bits 1 and 0 select the clock supplied to the 14-bit PWM. These bits are write-only bits; they are
always read as 1.
Bit 1
Bit 0
PWCR1
PWCR0
Description
0
0
The input clock is ø/2 (tø
*
= 2/ø)
(initial value)
The conversion period is 16,384/ø, with a minimum
modulation width of 1/ø
0
1
The input clock is ø/4 (tø
*
= 4/ø)
The conversion period is 32,768/ø, with a minimum
modulation width of 2/ø
1
0
The input clock is ø/8 (tø
*
= 8/ø)
The conversion period is 65,536/ø, with a minimum
modulation width of 4/ø
1
1
The input clock is ø/16 (tø
*
= 16/ø)
The conversion period is 131,072/ø, with a minimum
modulation width of 8/ø
Note:
*
Period of PWM input clock.
Bit
Initial value
Read/Write
7
—
1
—
6
—
1
—
5
—
1
—
4
—
1
—
3
—
1
—
0
PWCR0
0
W
2
—
1
—
1
PWCR1
0
W
307