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2 pwm compare register (comr), Pwm compare register (comr) – FUJITSU F2MC-8L F202RA User Manual

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CHAPTER 7 8-BIT PWM TIMER

7.4.2

PWM Compare Register (COMR)

The PWM compare register (COMR) is used to set an interval while the internal timer
functions are enabled. In addition, the register becomes the "H" level width of a pulse
while the PWM timer functions are enabled.

PWM Compare Register (COMR)

Figure 7.4-3 shows the bit configuration of a PWM compare register. Because this register is a write-only

register, an instruction to operate bits cannot be used.

Figure 7.4-3 PWM Compare Register (COMR)

While the interval timer is operating:

Specify an interval in the register to which the value compared with the counter value is to be set.

When the settings written to this register match the counter value, the counter is cleared and "1" is set to the

interrupt request flag bit (CNTR: TIR = 1).

If a value is written to the COMR register while the counter is operating, the value takes effect at the next

cycle (after detection of a match).

Note:

The settings of the COMR register, while the interval timer is operating, can be calculated using the

following formula. The gear function, however, affects the instruction cycle.

COMR register value = interval/(count clock cycle

× instruction cycle) - 1

bit7

bit6

bit5

bit4

bit3

bit2

bit1

bit0

0023

H

XXXXXXXX

B

W

W

W

W

W

W

W

W

W
X

Address

Initial value

: Write only
: Undefined

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