h8s-2138 Renesas Electronics Corporation., h8s-2138 Datasheet - Page 323

• Manufacturer Part Number: h8s-2138
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

11.1
The H8S/2138 Group and H8S/2134 Group have a single-channel on-chip 16-bit free-running
timer (FRT) module that uses a 16-bit free-running counter as a time base. Applications of the
FRT module include rectangular-wave output (up to two independent waveforms), input pulse
width measurement, and measurement of external clock periods.
11.1.1
The features of the free-running timer module are listed below.
Selection of four clock sources
Two independent comparators
Four input capture channels
Counter can be cleared under program control
Seven independent interrupts
Special functions provided by automatic addition function
The free-running counter can be driven by an internal clock source ( /2, /8, or /32), or an
external clock input (enabling use as an external event counter).
Each comparator can generate an independent waveform.
The current count can be captured on the rising or falling edge (selectable) of an input
signal.
The four input capture registers can be used separately, or in a buffer mode.
The free-running counters can be cleared on compare-match A.
Two compare-match interrupts, four input capture interrupts, and one overflow interrupt
can be requested independently.
The contents of OCRAR and OCRAF can be added to the contents of OCRA
automatically, enabling a periodic waveform to be generated without software intervention.
The contents of ICRD can be added automatically to the contents of OCRDM
input capture operations in this interval to be restricted.
Overview
Features
Section 11 16-Bit Free-Running Timer
Rev. 4.00 Jun 06, 2006 page 269 of 1004
Section 11 16-Bit Free-Running Timer
REJ09B0301-0400
2, enabling