M16C62_M Datasheet, PDF (324/615 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

Timer A
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(2) Count source
The internal count source can be selected from f1, f8, f32, and fC32. Clocks f1, f8, and f32 are derived
by dividing the CPU's main clock by 1, 8, and 32 respectively. Clock fC32 is derived by dividing the
CPU's secondary clock by 32.
(3) Count value
In timer mode or pulse width modulation mode, [the value set in the timer register + 1] becomes the
count value. In event counter mode, [the set value + 1] becomes the count value when a down count
is performed, or [FFFF16 - the set value + 1] becomes the count value when an up count is performed.
In one-shot timer mode, the value set in the timer register becomes the count value.
The counter overflows (or underflows) when a count source equal to a count value is input, and an
interrupt occurs. For the pulse output function, the output from the port varies (the value in the port
register does not vary).
(4) Reading the timer
Either in timer mode or in event counter mode, reading the timer register takes out the count at that
moment. Read it in 16-bit units. The data either in one-shot timer mode or in pulse width modulation
mode is indeterminate.
(5) Writing to the timer
To write to the timer register when a count is in progress, the value is written only to the reload register.
When writing to the timer register when a count is stopped, the value is written both to the reload
register and to the counter. Write a value in 16-bit units.
(6) Relation between the input/output to/from the timer and the direction register
With the output function of the timer, pulses are output regardless of the direction register of the
relevant port. To input an external signal to the timer, set the direction register of the relevant port to
input.
(7) Pins related to timer A
(a) TA0IN, TA1IN, TA2IN, TA3IN, TA4IN
Input pins to timer A.
(b) TA0OUT, TA1OUT, TA2OUT, TA3OUT, TA4OUT Output pins from timer A. They become input pins to
timer A when event counter mode is active.
(8) Registers related to timer A
Figure 2.2.1 shows the memory map of timer A-related registers. Figures 2.2.2 through 2.2.5 show
timer A-related registers.
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