PULSE OUTPUT PORT MODE
9.3 Setting of pulse output port mode
From preceding “Figure 9.3.3”
When pulse width modulation is not performed
When pulse width modulation is performed
b7
b0
Timer Aj mode register (j = 1, 2, 4) (Addresses 5716, 5816, 5A16
)
0
0
1 1
j = 1, 2 : Fix this bit to “0.”
j = 4 : When not using pin TA4OUT (in other words, when using pin
P20 as a programmable I/O port pin), clear this bit to “0.”
16/8-bit PWM mode select bit
0 : 16-bit pulse width modulator
1 : 8-bit pulse width modulator
Count source select bits
See Table 7.2.3.
Setting of PWM pulse period and “H” level width
➀➀When 16-bit pulse width modulator
(b15)
b7
(b8)
b0 b7
Timer A1 register (Addresses 4916, 4816
)
b0
Timer A2 register (Addresses 4B16, 4A16
Timer A4 register (Addresses 4F16, 4E16
)
)
A value in the range from “000016 to FFFE16” (n) is set.
➀➀When 8-bit pulse width modulator
(b15)
b7
(b8)
b0 b7
Timer A1 register (Addresses 4916, 4816
Timer A2 register (Addresses 4B16, 4A16
Timer A4 register (Addresses 4F16, 4E16
)
)
)
b0
A value in the range from “0016” to “FF16” (m) is set.
A value in the range from “0016” to “FE16” (n) is set.
➀ When operating as 16-bit pulse width modulator
➀ When operating as 8-bit pulse width modulator
(m + 1)(28– 1)
216 – 1
fi
Period =
Period =
fi
n
fi
n (m + 1)
“H” level width =
“H” level width =
fi
fi : Frequency of count source
fi : Frequency of count source
However, if n = “000016,” the pulse width modulator
does not operate and pin TAjOUT pin outputs “L”
level. At this time, no timer Aj interrupt request
occurs.
However, if n = “0016,” the pulse width modulator
does not operate and pin TAjOUT pin outputs “L”
level. At this time, no timer Aj interrupt request
occurs.
Continue to “Figure 9.3.5.”
Fig. 9.3.4 Initial setting example for registers relevant to pulse output port mode (in pulse mode 1) (4)
7906 Group User’s Manual Rev.2.0
9-17
RENESAS [ RENESAS TECHNOLOGY CORP ]
