Hitachi H8S/2646 Hardware Manual page 767

Bit 5—Noise Elimination Sampling Frequency Select (NESEL): This bit selects the sampling
frequency of the subclock (øSUB) generated by the subclock oscillator is sampled by the clock (ø)
generated by the system clock oscillator. Set this bit to 0 when ø=5MHz or more. This setting is
disabled in sub-active mode, sub-sleep mode, and watch mode.
Bit 5
NESEL Description
0 Sampling using 1/32 xø
1 Sampling using 1/4 xø
Bit 4—Subclock enable (SUBSTP): This bit enables/disables subclock generation.
Bit 4
SUBSTP Description
0 Enables subclock generation
1 Disables subclock generation
Bit 3—Oscillation Circuit Feedback Resistance Control Bit (RFCUT): This bit turns the
internal feedback resistance of the main clock oscillation circuit ON/OFF.
Bit 3
RFCUT Description
0 When the main clock is oscillating, sets the feedback resistance ON. When the main
clock is stopped, sets the feedback resistance OFF.
1 Sets the feedback resistance OFF.
Bit 2—Reserved: Only write 0 to this bit.
(Initial value)
(Initial value)
(Initial value)
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