ATA6612C View Datasheet(PDF) - Atmel Corporation

Part Name

Description

MFG CO.

ATA6612C

8K/16K Flash Microcontroller with LIN Transceiver, 5V Regulator and Watchdog

Atmel Corporation 

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The user should poll the EEPE bit before starting the read operation. If a write operation is in progress, it is neither possible

to read the EEPROM, nor to change the EEAR register.

The calibrated oscillator is used to time the EEPROM accesses. Table 5-3 lists the typical programming time for EEPROM

access from the CPU.

Table 5-3. EEPROM Programming Time

Symbol

EEPROM write (from CPU)

Number of Calibrated RC Oscillator Cycles

26,368

Typ Programming Time

3.3ms

The following code examples show one assembly and one C function for writing to the EEPROM. The examples assume

that interrupts are controlled (e.g. by disabling interrupts 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

EEPROM_write:

; Wait for completion of previous write

sbic EECR,EEPE

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 EEMPE

sbi

EECR,EEMPE

; Start eeprom write by setting EEPE

sbi

EECR,EEPE

ret

C Code Example

void EEPROM_write(unsigned int uiAddress, unsigned char ucData)

{

/* Wait for completion of previous write */

while(EECR & (1<<EEPE))

;

/* Set up address and Data Registers */

EEAR = uiAddress;

EEDR = ucData;

/* Write logical one to EEMPE */

EECR |= (1<<EEMPE);

/* Start eeprom write by setting EEPE */

EECR |= (1<<EEPE);

}

ATA6612C/ATA6613C [DATASHEET]

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