SH7014 datasheet(260/754 Pages) RENESAS

260 / 754 page

10. Multifunction Timer Pulse Unit (MTU)

Rev.5.00 Sep. 27, 2007 Page 226 of 716

REJ09B0398-0500

10.4

Operation

10.4.1

Overview

The operation modes are described below.

Ordinary Operation: Each channel has a timer counter (TCNT) and general register (TGR). The

TCNT is an upcounter and can also operate as a free-running counter, periodic counter or external

event counter. General registers (TGR) can be used as output compare registers or input capture

registers.

Synchronized Operation: The TCNT of a channel set for synchronized operation does a

synchronized preset. When any TCNT of a channel operating in the synchronized mode is

rewritten, the TCNTs of other channels are simultaneously rewritten as well. The timer

synchronization bits of the TSYR registers of multiple channels set for synchronous operation can

be set to clear the TCNTs simultaneously.

Buffer Operation: When TGR is an output compare register, the buffer register value of the

corresponding channel is transferred to the TGR when a compare-match occurs. When TGR is an

input capture register, the TCNT counter value is transferred to the TGR when an input capture

occur simultaneously the value previously stored in the TGR is transferred to the buffer register.

Cascade Connection Operation: The channel 1 and channel 2 counters (TCNT1 and TCNT2)

can be connected together to operate as a 32-bit counter.

PWM Mode: In PWM mode, a PWM waveform is output. The output level can be set by the

TIOR register. Each TGR can be set for PWM waveform output with a duty cycle between 0

and 100

Phase Counting Mode: In phase counting mode, the phase differential between two clocks input

from the channel 1 and channel 2 external clock input pins is detected and the TCNT counter

operates as an up/down counter. In phase counting mode, the corresponding TCLK pins become

clock inputs and TCNT functions as an up/down counter. It can be used as a two-phase encoder

pulse input.

10.4.2

Basic Functions

Always select MTU external pin set function using the pin function controller (PFC).

Counter Operation: When a start bit (CST0 to CST2) in the timer start register (TSTR) is set to

1, the corresponding timer counter (TCNT) starts counting. There are two counting modes: a free-

running mode and a periodic mode.

SH7014 Datasheet(PDF) 260 Page - Renesas Technology Corp