HD6433802H Datasheet, PDF (296/435 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

11.2 Register Descriptions
11.2.1 PWM Control Register (PWCRm)
Bit
7
6
5
4
3
2
1
0
—
—
—
—
—
— PWCRm1 PWCRm0
Initial value
1
1
1
1
1
1
0
0
Read/Write
—
—
—
—
—
—
W
W
PWCRm is an 8-bit write-only register for input clock selection.
Upon reset, PWCRm 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 (PWCRm1, PWCRm0)
Bits 1 and 0 select the clock supplied to the 10-bit PWM. These bits are write-only bits; they are
always read as 1.
Bit 1
Bit 0
PWCRm1 PWCRm0 Description
0
0
The input clock is ø (tø* = 1/ø)
(initial value)
The conversion period is 512/ø, with a minimum modulation
width of 1/2ø
0
1
The input clock is ø/2 (tø* = 2/ø)
The conversion period is 1,024/ø, with a minimum
modulation width of 1/ø
1
0
The input clock is ø/4 (tø* = 4/ø)
The conversion period is 2,048/ø, with a minimum
modulation width of 2/ø
1
1
The input clock is ø/8 (tø* = 8/ø)
The conversion period is 4,096/ø, with a minimum
modulation width of 4/ø
Note: * Period of PWM input clock.
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