ATmega644R212 Atmel Corporation, ATmega644R212 Datasheet - Page 56

• Manufacturer Part Number: ATmega644R212
• Manufacturer: Atmel Corporation

Specifications of ATmega644R212

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 20 MHz
• Max I/o Pins: 32
• Spi: 3
• Twi (i2c): 1
• Uart: 1
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Crypto Engine: AES
• Sram (kbytes): 4
• Eeprom (bytes): 2048
• Operating Voltage (vcc): 1.8 to 3.6
• Timers: 3
• Frequency Band: 700/800/900MHz
• Max Data Rate (mb/s): 1
• Antenna Diversity: No
• External Pa Control: Yes
• Power Output (dbm): 10
• Receiver Sensitivity (dbm): -110
• Receive Current Consumption (ma): 9.0
• Transmit Current Consumption (ma): 18 at 5dBm
• Link Budget (dbm): 120

8011O–AVR–07/10
1. In the same operation, write a logic one to the Watchdog change enable bit (WDCE) and
2. Within the next four clock cycles, write the WDE and Watchdog prescaler bits (WDP) as
The following code example shows one assembly and one C function for turning off the Watch-
dog Timer. The example assumes that interrupts are controlled (for example by disabling
interrupts globally) so that no interrupts will occur during the execution of these functions.
Note:
Assembly Code Example
C Code Example
WDE. A logic one must be written to WDE regardless of the previous value of the WDE
bit.
desired, but with the WDCE bit cleared. This must be done in one operation.
WDT_off:
void WDT_off(void)
{
}
; Turn off global interrupt
cli
; Reset Watchdog Timer
wdr
; Clear WDRF in MCUSR
in
andi
out
; Write logical one to WDCE and WDE
; Keep old prescaler setting to prevent unintentional time-out
in
ori
out
; Turn off WDT
ldi
out
; Turn on global interrupt
sei
ret
__disable_interrupt();
__watchdog_reset();
/* Clear WDRF in MCUSR */
MCUSR &= ~(1<<WDRF);
/* Write logical one to WDCE and WDE */
/* Keep old prescaler setting to prevent unintentional time-out */
WDTCSR |= (1<<WDCE) | (1<<WDE);
/* Turn off WDT */
WDTCSR = 0x00;
__enable_interrupt();
1. The example code assumes that the part specific header file is included.
r16, MCUSR
r16, (0xff & (0<<WDRF))
MCUSR, r16
r16, WDTCSR
r16, (1<<WDCE) | (1<<WDE)
WDTCSR, r16
r16, (0<<WDE)
WDTCSR, r16
(1)
(1)
ATmega164P/324P/644P
56