deveopmen
Three-phase motor control timers’ functions
Preliminary Specifications REV.D
Specifications in this manual are tentative and subject to change.
Mitsubishi microcomputers
M16C/80 (100-pin version) group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
108
Three-phase motor control timers’ functions
Use of more than one built-in timer A and timer B provides the means of outputting three-phase motor
driving waveforms.
Figures 1.15.1 through 1.15.3 show registers related to timers for three-phase motor control.
No value other than “0” can be written.
Selecting three-phase PWM output mode causes the dead time timer, the U, V, W phase output control circuits, and the
timer B2 interrupt frequency set circuit works.
For U, U, V, V, W and W output from P8
0
, P8
1
, and P7
2
through P7
5
, setting of port function select register, peripheral
function select register and peripheral subfunction select regoster are required.
In triangular wave modulation mode:
The dead time timer starts in synchronization with the falling edge of timer Ai
output. The data transfer from the three-phase buffer register to the three-phase output shift register is made only once in
synchronization with the transfer trigger signal after writing to the three-phase output buffer register.
In sawtooth wave modulation mode:
The dead time timer starts in synchronization with the falling edge of timer A
output and with the transfer trigger signal. The data transfer from the three-phase output buffer register to the three-
phase output shift register is made with respect to every transfer trigger.
Set bit 1 of this register to "1" after setting timer B2 interrupt frequency set counter.
Three-phase PWM control register 0
b7
b6
b5
b4 b3
b2
b1
Symbol
INVC0
Address
0308
16
When reset
00
16
b0
Effective interrupt output
polarity select bit
INV0
0
Bit symbol
Bit name
Description
R
W
INV0
1
Effective interrupt output
specification bit
INV0
2
Mode select bit
(Note 2)
INV0
4
Positive and negative
phases concurrent L output
disable function enable bit
INV0
7
Software trigger bit
INV0
6
Modulation mode select
bit (Note 3)
INV0
5
Positive and negative
phases concurrent L output
detect flag
INV0
3
Output control
bit
0: A timer B2 interrupt occurs when the
timer A1 reload control signal is “0”.
1: A timer B2 interrupt occurs when the
timer A1 reload control signal is “1”.
Effective only in three-phase mode 1
0: Not specified.
1: Selected by the effective interrupt
output polarity selection bit.
Effective only in three-phase mode 1
0: Normal mode
1: Three-phase PWM output mode
0: Output disabled
1: Output enabled
0: Feature disabled
1: Feature enabled
0: Not detected yet
1: Already detected
0: Triangular wave modulation mode
1: Sawtooth wave modulation mode
1: Trigger generated
The value, when read, is “0”.
(Note 1)
T
hree-phase PWM control register 1
b7 b6
b5
b4
b3
b2
b1 b0
Symbol
INVC1
Address
0309
16
When reset
XXX0X000
2
Bit name
Description
Bit symbol
W
R
INV1
0
INV1
1
INV1
2
Timer Ai start trigger
signal select bit
Timer A1-1, A2-1, A4-1
control bit
Dead time timer count
source select bit
0: Timer B2 overflow signal
1: Timer B2 overflow signal,
signal for writing to timer B2
0: Three-phase mode 0
1: Three-phase mode 1
0 : Inhibit
1 : f
1
/2 (Note)
Noting is assigned.
When write, set "0". When read, their contents are "0".
Note 1:
Note 2:
Note 3:
Note 4:
Note : INV1
2
is valid when INV0
6
= 0 and INV1
1
= 1.
INV1
3
INV1
4
Carrier wave detect flag
Output porality control bit
0: Rising edge of triangular waveform
1: Falling edge of triangular waveform
0 : Low active
1 : High active
Figure 1.15.1. Registers related to timers for three-phase motor control