M37754 Mitsubishi, M37754 Datasheet - Page 36

• Manufacturer Part Number: M37754
• Description: SINGLE-CHIP 16BIT CMOS MICROCOMPUTER
• Manufacturer: Mitsubishi

Timer function for motor control
Three-phase motor drive waveform and pulse motor drive waveform
can be output by using plural internal timers A and B. Those modes
are explained bellow.
Three-phase motor drive waveform output
mode (three-phase waveform mode)
Three-phase waveform mode using four timers of the timers A0, A1,
A2 and B4 is selected by setting the waveform output select bits of
the waveform output mode register (address 1A
“100
There are two types of the three-phase waveform mode: three-
phase mode 0 and three-phase mode 1. Bit 4 of the waveform out-
put mode register selects either mode. In three-phase waveform
mode, set the corresponding timer mode registers of timers A0, A1,
and A2 to select the one-shot pulse mode with the rising edge of ex-
ternal trigger; set the timer mode register of timer B2 to select the
timer mode.
Figure 43 shows the three-phase waveform mode block diagram.
The three-phase waveform mode outputs six waveforms, positive
waveforms (U, V, W phases) and negative waveforms (U, V, W
phases), from the respective ports with “L” level active.
Timer A2 controls U and U phases; timer A1 does V and V phases
and timer A0 does W and W phases. Timer B2 controls those one-
shot pulses’ period of timers A2, A1 and A0.
In the waveform output, a short circuit prevention time can be set to
prevent “L” level of positive waveforms (U, V, W phases) from over-
lapping with “L” level of their negative waveforms (U, V, W phases).
The short circuit prevention time can be set with three 8-bit dead-
time timers, sharing one reload register. The dead-time timer oper-
ates as a one-shot timer. As its start trigger, both the rising and falling
edges of timers A0 to A2’s one-shot pulses or their falling edge. Bit 6
of the waveform output mode register selects it. When that is “0”,
both the rising and falling edges become the start trigger; when that
is “1”, the falling edge becomes it.
36
2
”.
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16
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,
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M37754M8C-XXXGP, M37754M8C-XXXHP
Figure 41) to
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Fig. 41 Waveform output mode register bit configuration
Fig. 42 Timer A0, A1, A2, mode register and timer B2 mode regis-
7
M37754S4CGP, M37754S4CHP
7
7
Note : Only when bit 5 of the particular function select register 1
6
6
6
5
ter bit configuration
(in Fig. 15) is set to “1”, this register’s contents can be changed
from the status during reset (in Fig.76).
5
0
5
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
4
4
1
4
3
3
1
3
2
1
2
2
1
0
1
1
1
0
MITSUBISHI MICROCOMPUTERS
0
0
0
0
0
0
Waveform output mode register
Waveform output select bits
(Valid in three-phase mode 1)
Three-phase output polarity set buffer
Three-phase mode select bit
Not used in three-phase
waveform mode
Dead-time timer trigger select bit
Waveform output control bit
100 : Fix to “100” in three-phase
0 : “H” output
1 : “L” output
0 : Three-phase mode 0
1 : Three-phase mode 1
0 : Both edge of one-shot pulse
1 : Only the falling edge of one-shot
0 : Waveform output disabled
1 : Waveform output enabled
Timer A0 mode register 56
Timer A1 mode register 57
Timer A2 mode register 58
Fix to “10” in three-phase
waveform mode
Fix to “1” in timers A0, A1
in timer A2
Fix to “011” in three-phase
waveform mode
Clock source select bit
Timer B2 mode register
Fix to “00” in three-phase
waveform mode
Not used in three-phase
waveform mode
Clock source select bit
0 : No one-shot pulse output
1 : One-shot pulse output
0 0 : Select Pf
0 1 : Select Pf
1 0 : Select Pf
1 1 : Select Pf
0 0 : Select Pf
0 1 : Select Pf
1 0 : Select Pf
1 1 : Select Pf
with timers A2 to A0
pulse with timers A2 to A0
waveform mode
2
16
64
512
2
16
64
512
Address
16
16
16
Address
5D
16
Address
1A
16