Table of Contents
Advertisement
5.6.2 Count source
In the PWM mode, the count source select bits (bits 6 and 7 at addresses 56
source. Table 5.6.2 lists the count source frequency.
Table 5.6.2 Count source frequency
Count source
select bits
b6
b7
0
0
0
1
1
0
1
1
Clock source for peripheral devices select bit : bit 2 at address 5F
5.6.3 Trigger
When a trigger is generated, the TAi
can be selected as that trigger.
An internal trigger is selected when the trigger select bits (bits 4 and 3 at addresses 56
or "01
"; an external trigger is selected when the bits are "10
2
A trigger generated during outputting of PWM pulses is ignored and it does not affect the pulse output
operation.
(1) When selecting internal trigger
A trigger is generated when writing "1" to the count start bit (at address 40
(2) When selecting external trigger
A trigger is generated at the falling of the TAi
is "0," or at its rising when bit 3 is "1." However, the trigger input is accepted only when the count
start bit is "1."
When using an external trigger, set the port P5 and P6 direction registers' bits which correspond to
the TAi
pins for the input mode.
IN
f(X
Clock source for peripheral
devices select bit = "0"
Count source
Frequency
f
6.25 MHz
4
f
781.25 kHz
32
f
195.3125 kHz
128
f
24.4141 kHz
1024
pin starts outputting PWM pulses. An internal or an external trigger
OUT
7751 Group User's Manual
5.6 Pulse width modulation (PWM) mode
) = 25 MHz
IN
Clock source for peripheral
devices select bit = "1"
Count source
Frequency
f
12.5 MHz
2
f
1.5625 MHz
16
f
390.625 kHz
64
f
48.8281 kHz
512
" or "11
2
pin's input signal when bit 3 at addresses 56
IN
TIMER A
to 5A
) select the count
16
16
f(X
) = 40 MHz
IN
Clock source for peripheral
devices select bit = "0"
Count source
f
4
f
32
f
128
f
1024
16
16
."
2
).
16
Frequency
10 MHz
1.25 MHz
312.5 kHz
39.0625 kHz
to 5A
) are "00
"
16
2
to 5A
16
16
5–43
Advertisement
Table of Contents
