PD17012_15 Datasheet, PDF (138/320 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCONTROLLERS WITH DIGITAL TUNING SYSTEM HARDWARE

µPD17012, 17P012
12.4 12-Bit Timer
12.4.1 General
Figure 12-15 illustrates the 12-bit timer.
The 12-bit timer operates as a timer by counting the basic clock (100 kHz or 20 kHz) by using a 12-bit counter,
and comparing its count value with a value set in advance.
Figure 12-15. Outline of 12-Bit Timer
Clock select block
TMCK flag
Count block
TMRES flag
TMRPT flag
TMEN flag
4.5 MHz
Divider
Selector
DBF
TMOVF flag
12
Timer/counter
(TMC)
Set
Overflow
Match
Match detector
IRQTM
set signal
Timer modulo
register (TMM)
12
DBF
Remarks 1. TMCK (bit 0 of 12-bit timer clock select register; refer to Figure 12-16) sets the basic clock frequency.
2. TMEN (bit 0 of 12-bit timer control register; refer to Figure 12-17) starts/stops the 12-bit timer.
3. TMRES (bit 1 of 12-bit timer control register; refer to Figure 12-17) controls resetting the timer/counter.
4. TMRPT (bit 2 of 12-bit timer control register; refer to Figure 12-17) selects the modulo count mode/free-
run count mode.
5. TMOVF (bit 0 of 12-bit timer overflow register; refer to Figure 12-18) detects an overflow in the timer/
counter.
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Data Sheet U10101EJ4V0DS