ATmega88PA Automotive Atmel Corporation, ATmega88PA Automotive Datasheet - Page 115

• Manufacturer Part Number: ATmega88PA Automotive
• Manufacturer: Atmel Corporation

9223B–AVR–09/11
The following code examples show how to do an atomic write of the TCNT1 Register contents.
Writing any of the OCR1A/B or ICR1 Registers can be done by using the same principle.
Assembly Code Example
C Code Example
Note:
Atmel ATmega48PA/88PA/168PA [Preliminary]
TIM16_ReadTCNT1:
unsigned int TIM16_ReadTCNT1( void )
{
}
; Save global interrupt flag
in r18,SREG
; Disable interrupts
cli
; Read TCNT1 into r17:r16
in r16,TCNT1L
in r17,TCNT1H
; Restore global interrupt flag
out SREG,r18
ret
unsigned char sreg;
unsigned int i;
/* Save global interrupt flag */
sreg = SREG;
/* Disable interrupts */
_CLI();
/* Read TCNT1 into i */
i = TCNT1;
/* Restore global interrupt flag */
SREG = sreg;
return i;
1.
See ”About Code Examples” on page 7.
For I/O Registers located in extended I/O map, “IN”, “OUT”, “SBIS”, “SBIC”, “CBI”, and
“SBI” instructions must be replaced with instructions that allow access to extended I/O.
Typically “LDS” and “STS” combined with “SBRS”, “SBRC”, “SBR”, and “CBR”.
(1)
(1)
115