SAM7X256_14 Datasheet, PDF (408/662 Pages) ATMEL Corporation – ARM-based Flash MCU

33.3 I/O Lines Description
Each channel outputs one waveform on one external I/O line.
Table 33-1.
Name
PWMx
I/O Line Description
Description
PWM Waveform Output for channel x
Type
Output
33.4 Product Dependencies
33.4.1 I/O Lines
The pins used for interfacing the PWM may be multiplexed with PIO lines. The programmer must first program the PIO
controller to assign the desired PWM pins to their peripheral function. If I/O lines of the PWM are not used by the
application, they can be used for other purposes by the PIO controller.
All of the PWM outputs may or may not be enabled. If an application requires only four channels, then only four PIO lines
will be assigned to PWM outputs.
33.4.2 Power Management
The PWM is not continuously clocked. The programmer must first enable the PWM clock in the Power Management
Controller (PMC) before using the PWM. However, if the application does not require PWM operations, the PWM clock
can be stopped when not needed and be restarted later. In this case, the PWM will resume its operations where it left off.
Configuring the PWM does not require the PWM clock to be enabled.
33.4.3 Interrupt Sources
The PWM interrupt line is connected on one of the internal sources of the Advanced Interrupt Controller. Using the PWM
interrupt requires the AIC to be programmed first. Note that it is not recommended to use the PWM interrupt line in edge
sensitive mode.
33.5
Functional Description
The PWM macrocell is primarily composed of a clock generator module and 4 channels.
 Clocked by the system clock, MCK, the clock generator module provides 13 clocks.
 Each channel can independently choose one of the clock generator outputs.
 Each channel generates an output waveform with attributes that can be defined independently for each
channel through the user interface registers.
SAM7X Series [DATASHEET]
6120K–ATARM–11-Feb-14
408