Toshiba TLCS-900/H1 Series Data Book page 133

(4) 8-Bit PWM Output Mode
This mode is only valid for TMRA0. In this mode, a PWM pulse with the maximum
resolution of 8 bits can be output.
When TMRA0 is used the PWM pulse is output on the TA1OUT pin (which is also
used as PC1). TMRA1 can also be used as an 8-bit timer.
The timer output is inverted when the up-counter (UC0) matches the value set in the
timer register TA0REG or when 2
specified by TA01MOD<PWM01 to PWM00>). The up-counter UC0 is cleared when 2
−1 counter overflow occurs.
The following conditions must be satisfied before this PWM mode can be used.
Value set in TA0REG < value set for 2
Value set in TA0REG ≠ 0
TA0REG and
UC0 match
n
2 -1
overflow
(INTTA0 interrupt)
TA1OUT
Figure3.7.1 shows a block diagram representing this mode.
φT1
φT4
Selector
φT16
TA01MOD <TA0CLK1:0>
Selector
Shift trigger
TA0REG-WR
TA01RUN<TA0RDE>
Figure3.7.18 Block diagram of 8-Bit PWM Mode
n
−1 counter overflow occurs (n = 6, 7 or 8 as
Figure 3.4.17 8-bit PWM waveforms
TA01RUN <TA0RUN>
8-bit up counter
Cliar
(UC 0)
n
2
overflow
control
Comparator
TA0REG
Register buffer
Internal bus
92CH21 - 129
n
−1 counter overflow
t
PWM
(PWM cycle)
TA1OUT
-1
TA01MOD
<PWM01∼
PWM0100>
Overflow
TMP92CH21
TA1FFCR
TA1FF
<TAFF1IE>
Invert
INTTA0
n