Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet

Product codes
ATSAM4S-WPIR-RD
Page of 1231
SAM4S Series [DATASHEET]
Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14
928
39.
Pulse Width Modulation Controller (PWM)
39.1
Description
The PWM macrocell controls 4 channels independently. Each channel controls two complementary square output 
waveforms. Characteristics of the output waveforms such as period, duty-cycle, polarity and dead-times (also 
called dead-bands or non-overlapping times) are configured through the user interface. Each channel selects and 
uses one of the clocks provided by the clock generator. The clock generator provides several clocks resulting from 
the division of the PWM master clock (MCK).
All PWM macrocell accesses are made through registers mapped on the peripheral bus. All channels integrate a 
double buffering system in order to prevent an unexpected output waveform while modifying the period, the duty-
cycleor the dead-times.
Channels can be linked together as synchronous channels to be able to update their duty-cycle or dead-times at 
the same time.
The update of duty-cycles of synchronous channels can be performed by the Peripheral DMA Controller Channel 
(PDC) which offers buffer transfer without processor Intervention.
The PWM macrocell provides 8 independent comparison units capable of comparing a programmed value to the 
counter of the synchronous channels (counter of channel 0). These comparisons are intended to generate 
software interrupts, to trigger pulses on the 2 independent event lines (in order to synchronize ADC conversions 
with a lot of flexibility independently of the PWM outputs) and to trigger PDCtransfer requests.
The PWM outputs can be overridden synchronously or asynchronously to their channel counter.
The PWM block provides a fault protection mechanism with 8 fault inputs
capable to detect a fault condition and to 
override the PWM outputs asynchronously (outputs forced to ‘0’, ‘1’).
For safety usage, some configuration registers are write-protected.
39.2
Embedded Characteristics
4 Channels
Common Clock Generator Providing Thirteen Different Clocks 
̶
A Modulo n Counter Providing Eleven Clocks
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Two Independent Linear Dividers Working on Modulo n Counter Outputs
Independent Channels
̶
Independent 16-bit Counter for Each Channel
̶
Independent Complementary Outputs with 12-bit Dead-Time Generator (Also Called Dead-Band or 
Non-Overlapping Time) for Each Channel
̶
Independent Enable Disable Command for Each Channel
̶
Independent Clock Selection for Each Channel
̶
Independent Period, Duty-Cycle and Dead-Time for Each Channel
̶
Independent Double Buffering of Period, Duty-Cycle and Dead-Times for Each Channel
̶
Independent Programmable Selection of The Output Waveform Polarity for Each Channel
̶
Independent Programmable Center or Left Aligned Output Waveform for Each Channel
̶
Independent Output Override for Each Channel
̶
Independent Interrupt for Each Channel, at Each Period for Left-Aligned or Center-Aligned 
Configuration 
2
 2-bit Gray Up/Down Channels for Stepper Motor Control
Synchronous Channel Mode
̶
Synchronous Channels Share the Same Counter