ATTINY261-20SU Atmel, ATTINY261-20SU Datasheet - Page 82

• Manufacturer Part Number: ATTINY261-20SU
• Description: IC MCU AVR 2K FLASH 20MHZ 20SOIC
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY261-20SU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 11x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-SOIC (7.5mm Width)
• Processor Series: ATTINY2x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: SPI, USI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 16
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 55 C
• On-chip Adc: 10 bit, 11 Channel
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATAVRBC100 - REF DESIGN KIT BATTERY CHARGER770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATSTK505 - ADAPTER KIT FOR 14PIN AVR MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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ATtiny261/461/861
The following code examples show how to do an atomic read of the TCNT0 register contents.
Reading any of the OCR0 register can be done by using the same principle.
Note:
The assembly code example returns the TCNT0H/L value in the r17:r16 register pair.
Assembly Code Example
TIM0_ReadTCNT0:
C Code Example
unsigned int TIM0_ReadTCNT0( void )
{
}
; Save global interrupt flag
in r18,SREG
; Disable interrupts
cli
; Read TCNT0 into r17:r16
in r16,TCNT0L
in r17,TCNT0H
; Restore global interrupt flag
out SREG,r18
ret
unsigned char sreg;
unsigned int i;
/* Save global interrupt flag */
sreg = SREG;
/* Disable interrupts */
_CLI();
/* Read TCNT0 into i */
i = TCNT0L;
i |= ((unsigned int)TCNT0H << 8);
/* Restore global interrupt flag */
SREG = sreg;
return i;
See
“Code Examples” on page
6.
2588E–AVR–08/10