at90pwm81-16se ATMEL Corporation, at90pwm81-16se Datasheet - Page 159

• Manufacturer Part Number: at90pwm81-16se
• Description: 8-bit Avr Microcontroller With 8k Bytes In- System Programmable Flash
• Manufacturer: ATMEL Corporation

14.8.4
14.8.4.1
14.8.4.2
7734M–AVR–03/10
PSCR Input Configuration
Filter Enable
Signal Polarity
Figure 14-13. Burst Generation
The PSCR Input Configuration is done by programming bits in configuration registers.
If the “Filter Enable” bit is set, a digital filter of 4 cycles is inserted before evaluation of the signal. The
disable of this function is mainly needed for prescaled PSCR clock sources, where the noise cancellation
gives too high latency.
Important: If the digital filter is active, the level sensitivity is true also with a disturbed PSCR clock to
deactivate the outputs (emergency protection of external component). Likewise when used as fault input,
PSCr Input A or Input B have to go through PSCR to act on PSCOUTr0/1/2/3 output. This way needs that
CLK
can deactivate directly the PSCR output. Notice that in this case, input is still taken into account as usually
by Input Module System as soon as CLK
PSCR Input Flittering
One can select the active edge (edge modes) or the active level (level modes) See PELEV0x bit descrip-
tion in Section “PSCR Input A Control Register – PFRC0A”, page 17514.23.8.
PSCOUTn0
PSCOUTn1
PSCn Input A
(high level)
PSCn Input A
(low level)
PSCR
is running. So thanks to PSCR Asynchronous Output Control bit (PAOCrA/B), PSCrIN0/1 input
PSC Input
Module X
CLK
PSC
OFF
Digital
Filter
4 x CLK
PSCR
PSC
is running.
BURST
Ouput
Stage
PSCn Input A or B
PSCOUTnX
PIN
AT90PWM81
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