SH7261 datasheet(521/1348 Pages) RENESAS

521 / 1348 page

Section 12 Multi-Function Timer Pulse Unit 2 (MTU2)

Rev. 2.00 Sep. 07, 2007 Page 489 of 1312

REJ09B0320-0200

(3)

Phase Counting Mode Application Example:

Figure 12.34 shows an example in which channel 1 is in phase counting mode, and channel 1 is

coupled with channel 0 to input servo motor 2-phase encoder pulses in order to detect position or

speed.

Channel 1 is set to phase counting mode 1, and the encoder pulse A-phase and B-phase are input

to TCLKA and TCLKB.

Channel 0 operates with TCNT counter clearing by TGRC_0 compare match; TGRA_0 and

TGRC_0 are used for the compare match function and are set with the speed control period and

position control period. TGRB_0 is used for input capture, with TGRB_0 and TGRD_0 operating

in buffer mode. The channel 1 counter input clock is designated as the TGRB_0 input capture

source, and the pulse widths of 2-phase encoder 4-multiplication pulses are detected.

TGRA_1 and TGRB_1 for channel 1 are designated for input capture, and channel 0 TGRA_0 and

TGRC_0 compare matches are selected as the input capture source and store the up/down-counter

values for the control periods.

This procedure enables the accurate detection of position and speed.

TCNT_1

TCNT_0

Channel 1

TGRA_1

(speed period capture)

TGRA_0

(speed control period)

TGRB_1

(position period capture)

TGRC_0

(position control period)

TGRB_0 (pulse width capture)

TGRD_0 (buffer operation)

Channel 0

TCLKA

TCLKB

Edge

detection

circuit

Figure 12.34 Phase Counting Mode Application Example

SH7261 Datasheet(PDF) 521 Page - Renesas Technology Corp