ATmega406 Atmel Corporation, ATmega406 Datasheet - Page 50

• Manufacturer Part Number: ATmega406
• Manufacturer: Atmel Corporation

Specifications of ATmega406

• Flash (kbytes): 40 Kbytes
• Pin Count: 48
• Max. Operating Frequency: 1 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 8
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 18
• Ext Interrupts: 4
• Usb Speed: No
• Usb Interface: No
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 12
• Adc Speed (ksps): 1.9
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 2
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -30 to 85
• I/o Supply Class: 4.0 to 25
• Operating Voltage (vcc): 4.0 to 25
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 3
• Pwm Channels: 2
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

Table 10-1.
50
WUTP2
0
0
0
0
1
1
1
1
ATmega406
Wake-up Timer Prescale Select
WUTP1
0
0
1
1
0
0
1
1
• Bit 6 – WUTIE: Wake-up Timer Interrupt Enable
When the WUTIE bit and the I-bit in the Status Register are set (one), the Wake-up Timer inter-
rupt is enabled. The corresponding interrupt is executed if a Wake-up Timer overflow occurs,
i.e., when the WUTIF bit is set.
• Bit 5 – WUTCF: Wake-up Timer Calibration Flag
The WUTCF bit is set every 1.95 ms (256 Slow RC OScillator clocks or 64 32 kHz Crystal Oscil-
lator clocks). WUTCF is cleared by writing a logic one to the flag. WUTCF can be used to
calibrate the Fast RC Oscillator to the 32 kHz oscillator or the Slow RC Oscillator.
• Bit 4 – WUTR: Wake-up Timer Reset
When WUTR bit is written to one, the Wake-up Timer is reset, and starts counting from zero.
The WUTR bit is always read as zero.
• Bit 3 – WUTE: Wake-up Timer Enable
When the WUTE bit is set (one) the Wake-up Timer is enabled, and if the WUTE is cleared
(zero) the Wake-up Timer function is disabled. It is recommended to reset the Wake-up Timer
when enabling it, by simultaneously setting the WUTR and WUTE bits.
• Bits 2:0 – WUTP2, WUTP1, WUTP0: Wake-up Timer Prescaler 2, 1, and 0
The WUTP2, WUTP1 and WUTP0 bits determine the Wake-up Timer prescaling when the
Wake-up Timer is enabled. The different prescaling values and their corresponding time-out
periods are shown in
these bits.
WUTP0
0
1
0
1
0
1
0
1
Number of Slow RC
Oscillator Cycles
128K(131072)
256K(262144)
512K(524288)
16K(16384)
32K(32768)
64K(65536)
4K(4096)
8K(8192)
Table
10-1. The Wake-up Timer should always be reset when changing
Number of 32kHz Crystal
Oscillator Cycles
128K(131072)
16K(16384)
32K(32768)
64K(65536)
1K(1024)
2K(2048)
4K(4096)
8K(8192)
Typical Time-out
31.25 ms
62.5 ms
125 ms
250 ms
0.5 s
1 s
2 s
4 s
2548E–AVR–07/06