SAM3S4B Atmel Corporation, SAM3S4B Datasheet - Page 192

• Manufacturer Part Number: SAM3S4B
• Manufacturer: Atmel Corporation

Specifications of SAM3S4B

• Flash (kbytes): 256 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 64 MHz
• Cpu: Cortex-M3
• # Of Touch Channels: 23
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 79
• Ext Interrupts: 79
• Usb Transceiver: 1
• Quadrature Decoder Channels: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 3
• Twi (i2c): 2
• Uart: 4
• Ssc: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 10
• Adc Resolution (bits): 12
• Adc Speed (ksps): 1000
• Analog Comparators: 1
• Resistive Touch Screen: No
• Dac Channels: 2
• Dac Resolution (bits): 12
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 48
• Self Program Memory: YES
• 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

10.22.1
• COUNTFLAG
Returns 1 if timer counted to 0 since last time this was read.
• CLKSOURCE
Indicates the clock source:
0 = MCK/8
1 = MCK
• TICKINT
Enables SysTick exception request:
0 = counting down to zero does not assert the SysTick exception request
1 = counting down to zero to asserts the SysTick exception request.
Software can use COUNTFLAG to determine if SysTick has ever counted to zero.
• ENABLE
Enables the counter:
0 = counter disabled
1 = counter enabled.
When ENABLE is set to 1, the counter loads the RELOAD value from the LOAD register and then counts down. On reach-
ing 0, it sets the COUNTFLAG to 1 and optionally asserts the SysTick depending on the value of TICKINT. It then loads the
RELOAD value again, and begins counting.
192
31
23
15
7
SAM3S
SysTick Control and Status Register
30
22
14
6
The SysTick CTRL register enables the SysTick features. See the register summary in
33 on page 191
Reserved
29
21
13
5
for its attributes. The bit assignments are:
Reserved
28
20
12
4
Reserved
Reserved
27
19
11
3
CLKSOURCE
26
18
10
2
TICKINT
25
17
9
1
6500C–ATARM–8-Feb-11
COUNTFLAG
ENABLE
Table 10-
24
16
8
0