Function; 8-Bit Timer Mode (Tc3 And 4) - Toshiba TLCS-870/C Series Manual

9.3 Function

The TimerCounter 3 and 4 have the 8-bit timer, 8-bit event counter, 8-bit programmable divider output (PDO), 8-
bit pulse width modulation (PWM) output modes. The TimerCounter 3 and 4 (TC3, 4) are cascadable to form a 16-
bit timer. The 16-bit timer has the operating modes such as the 16-bit timer, 16-bit event counter, warm-up counter,
16-bit pulse width modulation (PWM) output and 16-bit programmable pulse generation (PPG) modes.

9.3.1 8-Bit Timer Mode (TC3 and 4)

In the timer mode, the up-counter counts up using the internal clock. When a match between the up-counter
and the timer register j (TTREGj) value is detected, an INTTCj interrupt is generated and the up-counter is
cleared. After being cleared, the up-counter restarts counting.
Note 1: In the timer mode, fix TCjCR<TFFj> to 0. If not fixed, the
Note 2: In the timer mode, do not change the TTREGj setting while the timer is running. Since TTREGj is not in the
shift register configuration in the timer mode, the new value programmed in TTREGj is in effect immediately
after the programming. Therefore, if TTREGi is changed while the timer is running, an expected operation
may not be obtained.
Note 3: j = 3, 4
Table 9-4 Source Clock for TimerCounter 3, 4 (Internal Clock)
Source Clock
NORMAL1/2, IDLE1/2 mode
DV7CK = 0 DV7CK = 1
11
fc/2 [Hz] fs/2
7
fc/2 fc/2
5
fc/2 fc/2
3
fc/2 fc/2
Example :Setting the timer mode with source clock fc/2
(TimerCounter4, fc = 16.0 MHz)
SLOW1/2,
SLEEP1/2
mode
3 3
[Hz] fs/2 [Hz]
7
–
5
–
3
–
7
LD (TTREG4), 0AH
DI
SET (EIRH). 3
EI
LD (TC4CR), 00010000B
LD (TC4CR), 00011000B
, and
PDOj PWMj
Resolution
fc = 16 MHz fs = 32.768 kHz
128 µs 244.14 µs
8 µs
–
2 µs
–
500 ns –
Hz and generating an interrupt 80 µs later
: Sets the timer register (80 µs
: Enables INTTC4 interrupt.
: Sets the operating clock to fc/2
: Starts TC4.
Page 87
TMP86PM29BUG
pins may output pulses.
PPGj
Maximum Time Setting
fc = 16 MHz fs = 32.768 kHz
32.6 ms 62.3 ms
2.0 ms –
510 µs
–
127.5 µs
–
÷
7
2 /fc = 0AH).
7
, and 8-bit timer mode.