M16C65 Datasheet, PDF (351/829 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/60

Under development
M16C/65 Group
Preliminary Specification
This is a preliminary specification and is subject to change.
17. Timer A
17.3.5 One-Shot Timer Mode
In one-shot timer mode, the timer is activated only once by one trigger. When the trigger occurs, the
timer starts and continues operating for a given period. Table 17.12 lists Specifications of One-Shot
Timer Mode. Table 17.13 lists Registers and the Setting in One-Shot Timer Mode. Figure 17.10 shows
Operation Example in One-Shot Timer Mode.
Table 17.12 Specifications of One-Shot Timer Mode
Item
Count source
Count operations
Pulse width
Count start condition
Count stop condition
Interrupt request
generation timing
TAiIN pin function
TAiOUT pin function
Read from timer
Write to timer
Selectable functions
i = 0 to 4
Specification
f1TIMAB, f2TIMAB, f8TIMAB, f32TIMAB, f64TIMAB, fOCO-F, fOCO-S, fC32
• Decrement
• When the counter reaches 0000h, it stops counting after reloading a new
value.
• When a trigger occurs while counting, the timer reloads a new value and
restarts counting.
n--
n
fj
n: set value of the TAi register 0000h to FFFFh
However, the counter does not work if 0000h is set.
fj: count source frequency
The TAiS bit in the TABSR register is 1 (start counting) and one of the following
triggers occurs:
• External trigger input from the TAiIN pin
• Timer B2 overflow or underflow
• Timer Aj overflow or underflow (j = i - 1, except j = 4 if i = 0)
• Timer Ak overflow or underflow (k = i + 1, except k = 0 if i = 4)
• The TAiOS bit in the ONSF register is set to 1 (timer starts).
• When the counter is reloaded after reaching 0000h
• The TAiS bit is set to 0 (stop counting)
When the counter reaches 0000h
I/O port or trigger input
I/O port or pulse output
An undefined value is read by reading the TAi register.
• When not counting and until the first count source is input after counting starts,
the value written to the TAi register is written to both reload register and
counter.
• When counting (after first count source input),
the value written to the TAi register is written to only the reload register
(transferred to the counter when reloaded next).
• Pulse output function
The timer outputs a low-level signal when not counting and a high-level signal
when counting.
• Output polarity control
The output polarity of TAiOUT pin is inverted. (While the TAiS bit is set to 0
(stop counting), the pin outputs a high-level signal.)
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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