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6 how do i clamp the ppg pin output level – FUJITSU MB91460 SERIES FR60 User Manual

Page 830

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814

Chapter 39 Programmable Pulse Generator

7.Q & A

7.5 What count clocks are available and how are they selected?

Count clock selection

The count clock is selectable out of the four choices listed below.

Use the count clock selection bit (PCN.CKS[1:0]).

(See “

8. Caution (Page No.821)

”.)

7.6 How do I clamp the PPG pin output level?

PPG output mask selection

The level of PPG pin output can be clamped.

Use the PPG Output Mask Selection bit (PCN.PGMS) and the duty value (PDUT) to set.

PPG pin output can be set to all “L”. (when OSEL=“0”)

PPG pin output can be set to all “H”. (when OSEL=“0”)

PPG output will also equal all “H” if “0” is set in both the PPG Period Setting Register (PCSR) and PPG Duty
Setting Register (PDUT). (when OSEL=“0”)

Count

Clock

Count Clock Selection Bit

(Example) CLKP = 32 MHz

CKS1

CKS0

Count Clock

Period (1 - FFFFh)

CLKP

0

0

32MHz

62.5ns - 2.048

µs

CLKP/4

0

1

8MHz

250ns - 8.192

µs

CLKP/16

1

0

2MHz

1

µs - 32.76ms

CLKP/64

1

1

500kHz

4

µs - 131.0ms

PPG Pin Output

PPG Output Polarity

Specification

Bit (OSEL)

Setting Procedure

To clamp the “L” level under normal polarity

When “0”

Set the PPG Output Mask Selection bit

(PGMS) to “1”.

To clamp the “H” level under normal polarity

When “0”

Period value (PCSR) =

Set a duty value (PDUT).

To clamp the “H” level under inverted polarity

When “1”

Set the PPG Output Mask Selection bit

(PGMS) to “1”.

To clamp the “L” level under inverted polarity

When “1”

Period value (PCSR) =

Set a duty value (PDUT).

PPG

Reduce
the duty
value

Write "1" to PGMS (mask bit) on occurrence
of an interrupt caused by a borrow.
If "0" is written to PGMS on occurrence of
an interrupt caused by a borrow, a PWM
waveform can be generated without
incurring hazard output.

PPG

Reduce
the duty value

Write the same value as the cycle setting
register value to the duty setting register
on occurrence of an interrupt caused by
a compare match.