ATTINY861A-SU Atmel, ATTINY861A-SU Datasheet - Page 108

• Manufacturer Part Number: ATTINY861A-SU
• Description: IC, MCU, 8BIT, 8K FLASH, 20SOIC
• Manufacturer: Atmel

Specifications of ATTINY861A-SU

• Controller Family/series: ATtiny
• No. Of I/o's: 16
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 20MHz
• No.: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 8KB
• Oscillator Type: External, Internal
• Rohs Compliant: Yes

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ATtiny261A/461A/861A
The following code examples show how to do an atomic read of the TCNT1 register contents.
Reading any of the OCR1A/B/C/D registers can be done by using the same principle.
Note:
The assembly code example returns the TCNT1 value in the r17:r16 register pair.
Assembly Code Example
TIM1_ReadTCNT1:
C Code Example
unsigned int TIM1_ReadTCNT1( void )
{
}
; Save global interrupt flag
in r18,SREG
; Disable interrupts
cli
; Read TCNT1 into r17:r16
in r16,TCNT1
in r17,TC1H
; 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;
i |= ((unsigned int)TC1H << 8);
/* Restore global interrupt flag
SREG = sreg;
return i;
See
“Code Examples” on page
6.
8197B–AVR–01/10