ATmega128A Atmel Corporation, ATmega128A Datasheet - Page 58

• Manufacturer Part Number: ATmega128A
• Manufacturer: Atmel Corporation

Specifications of ATmega128A

• Flash (kbytes): 128 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 53
• Ext Interrupts: 8
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 4
• Eeprom (bytes): 4096
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 4
• Output Compare Channels: 8
• Input Capture Channels: 2
• Pwm Channels: 7
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

8151H–AVR–02/11
Table 10-2.
The following code example shows one assembly and one C function for turning off the WDT.
The example assumes that interrupts are controlled (for example by disabling interrupts globally)
so that no interrupts will occur during execution of these functions.
Assembly Code Example
C Code Example
WDP2
0
0
0
0
1
1
1
1
WDT_off:
void WDT_off(void)
{
}
; Reset WDT
wdr
in r16, WDTCR
; Write logical one to WDCE and WDE
ori r16, (1<<WDCE)|(1<<WDE)
out WDTCR, r16
; Turn off WDT
ldi r16, (0<<WDE)
out WDTCR, r16
ret
/* Reset WDT*/
__watchdog_reset();
/* Write logical one to WDCE and WDE */
WDTCR |= (1<<WDCE) | (1<<WDE);
/* Turn off WDT */
WDTCR = 0x00;
WDP1
0
0
1
1
0
0
1
1
Watchdog Timer Prescale Select
WDP0
0
1
0
1
0
1
0
1
1,024K (1,048,576)
2,048K (2,097,152)
Oscillator Cycles
Number of WDT
128K (131,072)
256K (262,144)
512K (524,288)
16K (16,384)
32K (32,768)
64K (65,536)
Typical Time-out
at V
14.8ms
29.6ms
59.1ms
CC
0.12s
0.24s
0.47s
0.95s
1.9s
= 3.0V
ATmega128A
Typical Time-out
at V
14.0ms
28.1ms
56.2ms
0.11s
0.22s
0.45s
CC
0.9s
1.8s
= 5.0V
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