ATmega128A Atmel Corporation, ATmega128A Datasheet - Page 32

• 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
The calibrated Oscillator is used to time the EEPROM accesses.
gramming time for EEPROM access from the CPU.
Table 7-2.
Note:
The following code examples show one assembly and one C function for writing to the
EEPROM. The examples assume that interrupts are controlled (for example, by disabling inter-
rupts globally) so that no interrupts will occur during execution of these functions. The examples
also assume that no flash boot loader is present in the software. If such code is present, the
EEPROM write function must also wait for any ongoing SPM command to finish.
Assembly Code Example
C Code Example
EEPROM Write (from CPU)
EEPROM_write:
void EEPROM_write(unsigned int uiAddress, unsigned char ucData)
{
}
; Wait for completion of previous write
sbic EECR,EEWE
rjmp EEPROM_write
; Set up address (r18:r17) in address register
out EEARH, r18
out EEARL, r17
; Write data (r16) to data register
out EEDR,r16
; Write logical one to EEMWE
sbi EECR,EEMWE
; Start eeprom write by setting EEWE
sbi EECR,EEWE
ret
/* Wait for completion of previous write */
while(EECR & (1<<EEWE))
/* Set up address and data registers */
EEAR = uiAddress;
EEDR = ucData;
/* Write logical one to EEMWE */
EECR |= (1<<EEMWE);
/* Start eeprom write by setting EEWE */
EECR |= (1<<EEWE);
1. Uses 1MHz clock, independent of CKSEL-fuse settings.
;
Symbol
EEPROM Programming Time
Number of Calibrated RC Oscillator
Cycles
8448
(1)
Table 7-2
ATmega128A
Typ Programming Time
lists the typical pro-
8.5ms
32