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10.5.4
PWM Modes
In PWM mode, PWM waveforms are output from the output pins. 0, 1, or toggle output can be
selected as the output level in response to compare match of each TGR. Settings of TGR registers
can output a PWM waveform in the range of 0 % to 100 % duty. Designating TGR compare match
as the counter clearing source enables the period to be set in that register. All channels can be
designated for PWM mode independently. Synchronous operation is also possible. There are two
PWM modes, as described below.
• PWM mode 1
PWM output is generated from the TIOCA and TIOCC pins by pairing TGRA with TGRB and
TGRC with TGRD. The output specified by bits IOA3 to IOA0 and IOC3 to IOC0 in TIOR is
output from the TIOCA and TIOCC pins at compare matches A and C, and the output specified
by bits IOB3 to IOB0 and IOD3 to IOD0 in TIOR is output at compare matches B and D. The
initial output value is the value set in TGRA or TGRC. If the set values of paired TGRs are
identical, the output value does not change when a compare match occurs. In PWM mode 1, a
maximum 4-phase PWM output is possible.
• PWM mode 2
PWM output is generated using one TGR as the cycle register and the others as duty registers.
The output specified in TIOR is performed by means of compare matches. Upon counter
clearing by a synchronization register compare match, the output value of each pin is the initial
value set in TIOR. If the set values of the cycle and duty registers are identical, the output
value does not change when a compare match occurs. In PWM mode 2, a maximum 7-phase
PWM output is possible by combined use with synchronous operation. The correspondence
between PWM output pins and registers is shown in table 10.18.
Table 10.18 PWM Output Registers and Output Pins
Channel
0
1
2
Note: In PWM mode 2, PWM output is not possible for the TGR register in which the period is set.
Rev. 3.0, 10/02, page 302 of 686
Registers
TGRA_0
TGRB_0
TGRC_0
TGRD_0
TGRA_1
TGRB_1
TGRA_2
TGRB_2
Output Pins
PWM Mode 1
TIOCA0
TIOCC0
TIOCA1
TIOCA2
PWM Mode 2
TIOCA0
TIOCB0
TIOCC0
TIOCD0
TIOCA1
TIOCB1
TIOCA2
TIOCB2
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