Renesas H8SX/1650, Руководство по оборудованию

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Section 9 16-Bit Timer Pulse Unit (TPU)
Rev.2.00 Jun. 28, 2007 Page 369 of 666
REJ09B0311-0200
(3)
Phase Counting Mode Application Example
Figure 9.29 shows an example in which phase counting mode is designated for channel 1, and
channel 1 is coupled with channel 0 to input servo motor 2-phase encoder pulses in order to detect
the 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 cycle and
position control cycle. 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 width of 2-phase encoder 4-multiplication pulses is detected.
TGRA_1 and TGRB_1 for channel 1 are designated for input capture, channel 0 TGRA_0 and
TGRC_0 compare matches are selected as the input capture source, and the up/down-counter
values for the control cycles are stored.
This procedure enables accurate position/speed detection to be achieved.
TCNT_1
TCNT_0
Channel 1
TGRA_1
(speed cycle capture)
TGRA_0
(speed control cycle)
TGRB_1
(position cycle capture)
TGRC_0
(position control cycle)
TGRB_0 (pulse width capture)
TGRD_0 (buffer operation)
Channel 0
TCLKA
TCLKB
Edge
detection
circuit
+
-
+
-
Figure 9.29 Phase Counting Mode Application Example