
Timer A
M30240 Group
Rev.1.00 Sep 24, 2003 Page 168 of 360
Figure 2.28: Set-up procedure of pulse width modulation mode, 8-bit PWM mode selected
Setting PWM pulse's “H” level width
Can be set to 0016
to FE 16
b7
b0
(b15)
(b8)
b7
b0
Timer A0 register [Address 038716, 038616] TA0
Timer A1 register [Address 038916, 038816] TA1
Timer A2 register [Address 038B16, 038A16] TA2
Timer A3 register [Address 038D16, 038C16] TA3
Timer A4 register [Address 038F16, 038E16] TA4
Start count
Setting count starts flag
Count start flag [Address 0380 16]
TABSR
Timer A0 count start flag
Timer A1 count start flag
Timer A2 count start flag
Timer A3 count start flag
Timer A4 count start flag
b7
b0
Setting event/trigger select bit
One-shot start flag [Address 0382 16]
ONSF
Timer A0 event/trigger select bit
0 0 : Input on TA0 IN is selected (Note 2)
b7 b6
b7
b0
b7
b0
Timer A1 event/trigger select bit
0 0 : Input on TA1 IN is selected (Note 2)
b1 b0
Timer A2 event/trigger select bit
0 0 : Input on TA2 IN is selected (Note 2)
b3 b2
Timer A3 event/trigger select bit
0 0 : Input on TA3 IN is selected (Note 2)
b5 b4
Timer A4 event/trigger select bit
0 0 : Input on TA4 IN is selected (Note 2)
b7 b6
Note 2: Set the corresponding port direction register to “0”.
Trigger select register [Address 0383 16]
TRGSR
1 (Must always be “1” in PWM mode)
Selecting PWM mode and functions
Timer Ai mode register (i=0 to 4) [Address 0396 16 to 039A16]
TAiMR (i=0 to 4)
External trigger select bit
0 : Falling edge of TAi IN pin's input signal (Note 1)
Selection of PWM mode
b7
b0
11
01
1
16/8-bit PWM mode select bit
1 : Functions as a 8-bit pulse width modulator
b7 b6
Count source select bit
0 0 : f1
0 1 : f8
1 0 : f32
1 1 : Reserved
Trigger select bit
1 : Selected by event/trigger select register
Count source period
f(XIN) : 12MH Z
b7 b6
Count
source
83.3ns
667ns
2.67
s
00
01
10
f1
f8
f32
Note 1: Set the corresponding port direction
register to “0”.
Clearing timer Ai interrupt request bit
Timer Ai interrupt control register [Address 0055 16 to 005916]
TAiIC (i=0 to 4)
Interrupt request bit
b7
b0
0
Refer to 'Precaution for Timer A (pulse width modulation mode)'
1
Can be set to 0016 to FE16
Start count
Setting the TAiOUT drive capacity
Timer A output drive capacity register
[Address 03FB16 ]
TADR
Timer A0
OUT
drive capacity
Timer A1
Timer A2
Timer A3
Timer A4
b7
b0
OUT
drive capacity
OUT
drive capacity
OUT
drive capacity
OUT
drive capacity