SAM3U2C Atmel Corporation, SAM3U2C Datasheet - Page 784

no-image

SAM3U2C

Manufacturer Part Number
SAM3U2C
Description
Manufacturer
Atmel Corporation
Datasheets

Specifications of SAM3U2C

Flash (kbytes)
128 Kbytes
Pin Count
100
Max. Operating Frequency
96 MHz
Cpu
Cortex-M3
# Of Touch Channels
28
Hardware Qtouch Acquisition
No
Max I/o Pins
57
Ext Interrupts
57
Usb Transceiver
1
Quadrature Decoder Channels
1
Usb Speed
Hi-Speed
Usb Interface
Device
Spi
4
Twi (i2c)
1
Uart
4
Ssc
1
Sd / Emmc
1
Graphic Lcd
No
Video Decoder
No
Camera Interface
No
Adc Channels
8
Adc Resolution (bits)
12
Adc Speed (ksps)
384
Resistive Touch Screen
No
Temp. Sensor
No
Crypto Engine
No
Sram (kbytes)
36
Self Program Memory
YES
External Bus Interface
1
Dram Memory
No
Nand Interface
Yes
Picopower
No
Temp. Range (deg C)
-40 to 85
I/o Supply Class
1.8/3.3
Operating Voltage (vcc)
1.62 to 3.6
Fpu
No
Mpu / Mmu
Yes / No
Timers
3
Output Compare Channels
3
Input Capture Channels
3
Pwm Channels
4
32khz Rtc
Yes
Calibrated Rc Oscillator
Yes
36.6.14.5
784
784
SAM3U Series
SAM3U Series
Speed Measurement
In parallel, the number of edges are accumulated on timer/counter channel 0 and can be read on
the TC_CV0 register.
Therefore, the accurate position can be read on both TC_CV registers and concatenated to form
a 32-bit word.
The timer/counter channel 0 is cleared for each increment of IDX count value.
Depending on the quadrature signals, the direction is decoded and allows to count up or down in
timer/counter channels 0 and 1. The direction status is reported on TC_QISR register.
When SPEEDEN is set in TC_BMR register, the speed measure is enabled on channel 0.
A time base must be defined on channel 2 by writing the TC_RC2 period register. Channel 2
must be configured in waveform mode (WAVE bit field set) in TC_CMR2 register. WAVSEL bit
field must be defined with 0x10 to clear the counter by comparison and matching with TC_RC
value. ACPC field must be defined at 0x11 to toggle TIOA output.
This time base is automatically fed back to TIOA of channel 0 when QDEN and SPEEDEN are
set.
Channel 0 must be configured in capture mode (WAVE = 0 in TC_CMR0). ABETRG bit field of
TC_CMR0 must be configured at 1 to get TIOA as a trigger for this channel.
EDGTRG can be set to 0x01, to clear the counter on a rising edge of the TIOA signal and LDRA
field must be set accordingly to 0x01, to load TC_RA0 at the same time as the counter is cleared
(LDRB must be set to 0x01). As a consequence, at the end of each time base period the differ-
entiation required for the speed calculation is performed.
The process must be started by configuring the TC_CR register with CLKEN and SWTRG.
The speed can be read on TC_RA0 register in TC_CMR0.
Channel 1 can still be used to count the number of revolutions of the motor.
6430E–ATARM–29-Aug-11
6430E–ATARM–29-Aug-11

Related parts for SAM3U2C