
PULSE OUTPUT PORT MODE
7905 Group User’s Manual Rev.1.0
9-29
9.4 Setting of pulse output port mode
Fig. 9.4.4 Initial setting example for registers relevant to pulse output port 0 (pulse mode 1) (4)
b7
b0
11
b7
b0
(b15)
(b8)
b7
b0
b7
b0
(b15)
(b8)
b7
b0
0
Timer Ak mode register
(k = 6, 7, 9)
(Addresses D716, D816, DA16)
Timer A6 register (Addresses C916, C816)
Timer A7 register (Addresses CB16, CA16)
Timer A9 register (Addresses CF16, CE16)
Registers used in pulse output port 1
Continued from preceding Figure 9.4.3.
When pulse width modulation is not performed
When pulse width modulation is performed
Timer Aj mode register (j = 1, 2, 4) (Addresses 5716, 5816, 5A16)
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 bit
See Table 7.2.3.
Setting of PWM pulse period and “H” level width
When 16-bit pulse width modulator
Timer A1 register (Addresses 4916, 4816)
Timer A2 register (Addresses 4B16, 4A16)
Timer A4 register (Addresses 4F16, 4E16)
s When 8-bit pulse width modulator
s
A value in the range from “000016” to “FFFE16 ” (n) is set.
Timer A1 register (Addresses 4916, 4816)
Timer A2 register (Addresses 4B16, 4A16)
Timer A4 register (Addresses 4F16, 4E16)
A value in the range from “0016” to “FF16” (m) is set.
A value in the range from “0016” to “FE16” (n) is set.
(m + 1)(2 – 1)
fi
When operating as 8-bit pulse width modulator
“H” level width =
fi : Frequency of count source
Period =
8
n (m + 1)
fi
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.
2 – 1
fi
16
“H” level width =
fi : Frequency of count source
Period =
When operating as 16-bit pulse width modulator
n
fi
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.
Continued on Figure 9.4.5.
Timer A6 register (Addresses C916, C816)
Timer A7 register (Addresses CB16, CA16)
Timer A9 register (Addresses CF16, CE16)