SAM7L128 Atmel Corporation, SAM7L128 Datasheet - Page 457

• Manufacturer Part Number: SAM7L128
• Manufacturer: Atmel Corporation

Specifications of SAM7L128

• Flash (kbytes): 128 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 36 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 80
• Ext Interrupts: 80
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Segment Lcd: 40
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 460
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 6
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.8 to 3.6
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

6257A–ATARM–20-Feb-08
Figure 32-4. Non Overlapped Center Aligned Waveforms
Note:
When center aligned, the internal channel counter increases up to CPRD and.decreases down
to 0. This ends the period.
• the waveform duty cycle. This channel parameter is defined in the CDTY field of the
• the waveform polarity. At the beginning of the period, the signal can be at high or low level.
• the waveform alignment. The output waveform can be left or center aligned. Center aligned
If the waveform is center aligned then the output waveform period depends on the counter
source clock and can be calculated:
By using the Master Clock (MCK) divided by an X given prescaler value
(with X being 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, or 1024). The resulting period formula will
be:
By using a Master Clock divided by one of both DIVA or DIVB divider, the formula becomes,
respectively:
PWM_CDTYx register.
If the waveform is left aligned then:
If the waveform is center aligned, then:
This property is defined in the CPOL field of the PWM_CMRx register. By default the signal
starts by a low level.
waveforms can be used to generate non overlapped waveforms. This property is defined in
the CALG field of the PWM_CMRx register. The default mode is left aligned.
(
----------------------------------------- -
(
---------------------------------------- -
(
--------------------------------------------------- -
PWM0
PWM1
CRPD
2 X CPRD
2 CPRD
duty cycle
×
×
duty cycle
1. See
MCK
MCK
×
MCK
×
DIVA
×
Figure 32-5 on page 459
DIVA
No overlap
=
)
)
=
or
(
------------------------------------------------------------------------------------------------------- -
period 1 fchannel_x_clock
(
---------------------------------------------------------------------------------------------------------------------- -
)
(
period 2 ⁄
(
--------------------------------------------- -
CRPD
or
Period
(
--------------------------------------------------- -
2
–
MCK
×
×
CPRD
DIVAB
⁄
) 1 fchannel_x_clock
–
MCK
period
⁄
AT91SAM7L128/64 Preliminary
×
(
)
period 2 ⁄
DIVB
for a detailed description of center aligned waveforms.
)
)
×
CDTY
×
CDTY
)
) )
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