Timer G; Overview - Hitachi H8/3637 Hardware Manual

9.4

Timer G

9.4.1

Overview

Timer G is an 8-bit timer, with input capture/interval functions for separately capturing the rising
edge and falling edge of pulses input at the input capture pin (input capture input signal). Timer G
has a built-in noise canceller circuit that can eliminate high-frequency noise from the input capture
signal, enabling accurate measurement of its duty cycle. When timer G is not used for input
capture, it functions as an 8-bit interval timer.
Features: Features of timer G are given below.
• Choice of four internal clock sources (ø/64, ø/32, ø/2, ø
• Input capture function
Separate input capture functions are provided for the rising and falling edges.
• Counter overflow detection
Can detect whether overflow occurred when the input capture signal was high or low.
• Choice of counter clear
It is possible to select whether or not the counter is cleared at the rising edge, falling edge, or
both edges of the input capture input signal.
• Two interrupt sources
There is one input capture interrupt source and one overflow interrupt source. For input
capture, the rising or falling edge can be selected.
• Built-in noise-canceller circuit
The noise canceller circuit can eliminate high-frequency noise in the input capture signal.
• Operates in subactive and subsleep modes
When ø /2 is selected as the internal clock source, timer G can operate in the subactive and
W
subsleep modes.
/2)
W
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