HD6433308 Datasheet, PDF (188/349 Pages) Hitachi Semiconductor – Hitachi Single-Chip MicroComputer

The TCRs are 8-bit readable/writable registers that select the clock source and control the PWM
outputs.
The TCRs are initialized to H’38 at a reset and in the standby modes.
Bit 7 – Output Enable (OE): This bit enables the timer counter and the PWM output.
Bit 7
OE
0
1
Description
PWM output is disabled. TCNT is cleared to H’00 and stopped.
PWM output is enabled. TCNT runs.
(Initial value)
Bit 6 – Output Select (OS): This bit selects positive or negative logic for the PWM output.
Bit 6
OS
0
1
Description
Positive logic; positive-going PWM pulse, “1” = High
Negative logic; negative-going PWM pulse, “1” = Low
(Initial value)
Bits 5 to 3 – Reserved: These bits cannot be modified and are always read as “1.”
Bits 2, 1, and 0 – Clock Select (CKS2, CKS1, and CKS0): These bits select one of eight internal
clock sources obtained by dividing the system clock (Ø).
Bit 2
CKS2
0
0
0
0
1
1
1
1
Bit 1
CKS1
0
0
1
1
0
0
1
1
Bit 0
CKS0
0
1
0
1
0
1
0
1
Description
Ø/2
Ø/8
Ø/32
Ø/128
Ø/256
Ø/1024
Ø/2048
Ø/4096
(Initial value)
From the clock source frequency, the resolution, period, and frequency of the PWM output can be
calculated as follows.
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