H8S2245 datasheet(361/818 Pages) RENESAS

361 / 818 page

Section 9 16-Bit Timer Pulse Unit (TPU)

Rev.3.00 Mar. 26, 2007 Page 319 of 772

REJ09B0355-0300

9.4

Operation

9.4.1

Overview

Operation in each mode is outlined below.

Normal Operation

Each channel has a TCNT and TGR register. TCNT performs up-counting, and is also capable of

free-running operation, synchronous counting, and external event counting.

Each TGR can be used as an input capture register or output compare register.

Synchronous Operation

When synchronous operation is designated for a channel, TCNT for that channel performs

synchronous presetting. That is, when TCNT for a channel designated for synchronous operation

is rewritten, the TCNT counters for the other channels are also rewritten at the same time.

Synchronous clearing of the TCNT counters is also possible by setting the timer synchronization

bits in TSYR for channels designated for synchronous operation.

Buffer Operation

• When TGR is an output compare register

When a compare match occurs, the value in the buffer register for the relevant channel is

transferred to TGR.

• When TGR is an input capture register

When input capture occurs, the value in TCNT is transfer to TGR and the value previously

held in TGR is transferred to the buffer register.

PWM Mode

In this mode, a PWM waveform is output. The output level can be set by means of TIOR. A PWM

waveform with a duty of between 0% and 100% can be output, according to the setting of each

TGR register.

H8S2245 Datasheet(PDF) 361 Page - Renesas Technology Corp