MITSUBISHI MICROCOMPUTERS
M37754M8C-XXXGP, M37754M8C-XXXHP
M37754S4CGP, M37754S4CHP
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Three-phase mode 1
After the procedure above, three-phase mode 1 starts operation
In selecting three-phase waveform mode, three-phase mode 1 is
selected by setting bit 4 of the waveform output mode register (ad-
dress 1A16) to “1”.
when actuating the timer B2.
When the counter of timer B2 becomes 000016, the timer B2 inter-
rupt request occurs and timer A2 simultaneously starts one-shot
pulse output. At this time, the contents of three-phase output polarity
set buffer, “0” in this case, are set into the output polarity set toggle
flip-flop 2. The contents of three-phase output polarity set buffer are
reversed from “0” to “1” after that operation.
In this mode, each of timers A0 to A2 can have two timer registers
and the contents of those registers are alternately reloaded into the
counter each time the counter of timer B2 becomes 000016. About
write operation to two timer registers, when rewriting to each timer
register of timers A0, A1 and A2 after writing to each timer register of
them, the data is written each to timers A01, A11 andA21. When writ-
ing to each timer register, the timer A write register (in Figure 46) in-
dicates the timer to be intended for write.
When the timerA2 counter counts the value written into the timer A2
and the one-shot pulse output of timer A2 is completed, the contents
of output polarity set toggle flip-flop 2 are reversed from “0” to “1”. Si-
multaneously, the one-shot pulse of the 8-bit dead-time timer is out-
__
The interrupt request normally occurs when the counter of timer B2
becomes 000016. However, this occurrence interval can be switched
between “every second time” and “every fourth time.” Bit 0 of the
pulse output data register 1 (address 1C16) selects that.
Additionally, “0” or “1” of the three-phase output polarity set buffer
can be used as the occurrence factor of timer B2 interrupt request.
Bit 1 of the pulse output data register 1 (address 1C16) selects that.
When the timer B2’s counter contents become 000016, the contents
of three-phase output polarity set buffer are set into the output polar-
ity set toggle flip-flop on which .the output polarity of three-phase
waveform depends. The contents of three-phase output polarity set
buffer are reversed after that operation.
put for ensuring time, so that “L” levels of U- and U-phase waveforms
do not overlap.
7
6
5
4
3
2
1
0
Address
Timer A write register 4516
Timer A0 write bit
0 : Write to timer A0
1 : Write to timer A0
1
1
1
The polarity of the contents of output polarity set toggle flip-flop is re-
versed each time completion of one-shot pulse of timer (timers A2 to
A0) corresponding to each phase.
Timer A1 write bit
0 : Write to timer A1
1 : Write to timer A1
Figure 47 shows an example of U-phase waveform and the output
operation is explained.
Timer A2 write bit
0 : Write to timer A2
1 : Write to timer A2
Write “0” to the three-phase output polarity set buffer (bit 3 at ad-
dress 1A16). Clear the interrupt request interval set bit (bit 0 at ad-
dress 1C16) to “0” so that the timer B2 interrupt request may occur at
every second time. Additionally, clear the interrupt validity output se-
lect bit (bit 1 at address 1C16) so that the timer B2 interrupt request
may occur at “0” of the three-phase output polarity set buffer.
Note : Only when bit 5 of the particular function select register 1 (in Fig. 15)
is set to “1”, this register’s contents can be changed from the status
after reset (in Fig.76).
Fig. 46 Timer A write flag bit configuration
Timer B2 interrupt request
signal
Signal output each time
Timer B2 becomes 000016
One-shot pulse output with
n1
n1
n2
n2
n3
n3
n4
n5
n5
n6
n7
timer A2
Timer A2
Timer A2
1
n4
n6
n8
Contents of output polarity
set toggle flip-flop 2
Reversed pulse output
signal with dead-time timer
U-phase waveform output
U-phase waveform output
Fig. 47 U-phase waveform output example in three-phase mode 1 (triangular wave modulation)
40
RENESAS [ RENESAS TECHNOLOGY CORP ]
