ATmega406 Atmel Corporation, ATmega406 Datasheet - Page 170

• 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

170
ATmega406
Connect/Disconnect Interrupt is executed. If both SDA and SCL are high during reset, TWBCIF
will be set after reset. Otherwise TWBCIF will be cleared after reset.
• Bit 6 - TWBCIE: TWI Bus Connect/Disconnect Interrupt Enable
When the TWBCIE bit and the I-bit in the Status Register are set, the TWI Bus Connect/Discon-
ne ct In terr upt is e nab le d. Th e corre spon ding inte rrup t is execu ted if a TWI Bus
Connect/Disconnect occurs, i.e., when the TWBCIE bit is set.
• Bit 5:3 - Res: Reserved Bits
These bits are reserved bits in the ATmega406 and will always read as zero.
• Bit 2:1 - TWBDT1, TWBDT0: TWI Bus Disconnect Time-out Period
The TWBDT bits decides how long both the TWI data (SDA) and clock (SCL) signals must be
low before generating the TWI Bus Disconnect Interrupt. The different configuration values and
their corresponding time-out periods are shown in
Table 25-8.
• Bit 0 - TWBCIP: TWI Bus Connect/Disconnect Interrupt Polarity
The TWBCIP bit decide if the TWI Bus Connect/Disconnect Interrupt Flag (TWBCIF) should be
set on a Bus Connect or a Bus Disconnect. If TWBCIP is cleared, the TWBCIF flag is set on a
Bus Connect. If TWBCIP is set, the TWBCIF flag is set on a Bus Disconnect.
TWBDT1
0
0
1
1
TW Bus Disconnect Time-out Period
TWBDT0
0
1
0
1
TWI Bus Disconnect Time-out Period
250 ms
500 ms
1000 ms
2000 ms
Table
25-8.
2548E–AVR–07/06