SH7020 Datasheet, PDF (261/509 Pages) Renesas Technology Corp – SuperH™ RISC engine

PWM Mode: In PWM mode, a PWM waveform is output from the TIOCA pin. Output becomes
1 upon compare match A and 0 upon compare match B. GRA and GRB can be set so that the
PWM waveform output has a duty cycle between 0% and 100%. When set for PWM mode, the
GRA and GRB automatically become output compare registers.
Reset-synchronized PWM Mode: Three pairs of positive and negative PWM waveforms can be
obtained using channels 3 and 4 (the three phases of the PWM waveform share a transition point
on one side). When set for reset-synchronized PWM mode, GRA3, GRB3, GRA4, and GRB4
automatically become output compare registers. The TIOCA3, TIOCB3, TIOCA4, TOCXA4,
TIOCB4, and TOCXB4 pins also automatically become PWM output pins and TCNT3 becomes
an upcounter. TCNT4 functions independently (although GRA and GRB are isolated from
TCNT4).
Complementary PWM Mode: Three pairs of complementary positive and negative PWM
waveforms whose positive and negative phases do not overlap can be obtained using channels 3
and 4. When set for complementary PWM mode, GRA3, GRB3, GRA4, and GRB4 automatically
become output compare registers. The TIOCA3, TIOCB3, TIOCA4, TOCXA4, TIOCB4, and
TOCXB4 pins also automatically become PWM output pins while TCNT3 and TCNT4 become
upcounters.
Phase Counting Mode: In phase counting mode, the phase differential between two clocks input
from the TCLKA and TCLKB pins is detected and the TCNT2 operates as an up/downcounter. In
phase counting mode, the TCLKA and TCLKB pins become clock inputs and TCNT2 functions as
an up/downcounter.
Buffer Mode:
• When GR is an output compare register: The BR value of each channel is transferred to the GR
when a compare match occurs.
• When GR is an input capture register: The TCNT value is transferred to the GR when an input
capture occurs and simultaneously the value previously stored in the GR is transferred to the
BR.
• Complementary PWM mode: When the TCNT3 and TCNT4 change count directions, the BR
value is transferred to the GR.
• Reset-synchronized PWM mode: The BR value is transferred to GR upon a GRA3 compare
match.
10.4.2 Basic Functions
Counter Operation: When a start bit (STR0–STR4) 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.
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