Renesas M16C/60 Series Hardware Manual page 145

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M16C/6N5 Group
The three-phase motor control timer function is enabled by setting the INV02 bit of INVC0 register to "1".
When this function is selected, timer B2 is used to control the carrier wave, and timers A4, A1 and A2 are
used to control three-phase PWM outputs (U, U, V, V, W and W). The dead time is controlled by a
dedicated dead-time timer. Figure 1.14.9 shows the example of triangular modulation waveform and
Figure 1.14.10 shows the example of sawtooth modulation waveform.
Carrier wave: triangular waveform
Carrier wave
Signal wave
TB2S bit of the
TABSR register
Timer B2
Start trigger signal
for timer A4*
Timer A4
one-shot pulse*
U phase
output signal *
U phase
output signal *
U phase
INV14 = 0
("L" active)
U phase
U phase
INV14 = 1
("H" active)
U phase
INV13
(INV11 = 1 (three-phase
mode 1))
* Internal signals. See the block diagram of the three-phase motor control timer function.
Shown here is a typical waveform for the case where INVC0 = 00XX11XX
An example for changing PWM outputs is shown below.
(1)When INV11 = 1 (three-phase mode 1)
INV01 = 0, ICTB2 = 2 (timer B2 interrupt is generated at every
16
2'th occurrence of a timer B2 underflow), or INV01 = 1, INV00 = 1,
ICTB2=1 (timer B2 interrupt is generated at even-numbered
16
occurrences of a timer B2 underflow).
Initial timer value: TA41 = m, TA4 = m. The TA4 and TA41 registers
are modified every time a timer B2 interrupt occurs. First time,
TA41 = n, TA4 = n. Second time, TA41 = p, TA4 = p.
Initial values of IDB0 and IDB1 registers: DU0 = 1, DUB0 = 0,
DU1 = 0, DUB1 = 1.The register values are changed to DU0 = 1,
DUB0 = 0, DU1= 1 and DUB1 = 0 the third time a timer B2 interrupt
occurs.
The value written to the TA4 register and TA41 register are inverted at odd-numbered timer A outputs.
Figure 1.14.9 Triangular Wave Modulation Operation
Rev.1.00 2003.05.30 page 131
__
n
m m
(X = set as suitable for the system) and INVC1 = 010XXXX0
2
(2)When INV11 = 0 (three-phase mode 0)
INV01 = 0, ICTB2 = 1
of a timer B2 underflow)
Initial timer value: TA4 = m. The TA4 register is modified each time
a timer B2 interrupt occurs. First time, TA4 = m. Second time, TA4 = n.
Third time, TA4 = n. Fourth time, TA4 = p. Fifth time, TA4 = p.
Initial values of IDB0 and IDB1 registers: DU0 = 1, DUB0 = 0, DU1 = 0,
DUB1 = 1. The register values are changed to DU0 = 1, DUB0 = 0, DU1= 1
and DUB1 = 0 the sixth time a timer B2 interrupt occurs.
Three-phase Motor Control Timer Function
___ ___
p
p
n
Rewriting IDB0, IDB1 registers
Dead time
Dead time
(timer B2 interrupt is generated at every occurrence
16
Transfer to three-phase
output shift register
.
2