ATtiny25 Automotive Atmel Corporation, ATtiny25 Automotive Datasheet - Page 84

• Manufacturer Part Number: ATtiny25 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATtiny25 Automotive

• Flash (kbytes): 2 Kbytes
• Pin Count: 8
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 4
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 6
• Ext Interrupts: 6
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 125
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 5
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

14.1.1
84
ATtiny25/45/85
Timer/Counter1 Control Register - TCCR1
• Bit 7- CTC1 : Clear Timer/Counter on Compare Match
When the CTC1 control bit is set (one), Timer/Counter1 is reset to $00 in the CPU clock cycle
after a compare match with OCR1C register value. If the control bit is cleared, Timer/Counter1
continues counting and is unaffected by a compare match.
• Bit 6- PWM1A: Pulse Width Modulator A Enable
When set (one) this bit enables PWM mode based on comparator OCR1A in Timer/Counter1
and the counter value is reset to $00 in the CPU clock cycle after a compare match with OCR1C
register value.
• Bits 5,4 - COM1A1, COM1A0: Comparator A Output Mode, Bits 1 and 0
The COM1A1 and COM1A0 control bits determine any output pin action following a compare
match with compare register A in Timer/Counter1. Output pin actions affect pin PB1 (OC1A).
Since this is an alternative function to an I/O port, the corresponding direction control bit must be
set (one) in order to control an output pin. Note that OC1A is not connected in normal mode.
Table 14-1.
In PWM mode, these bits have different functions. Refer to
description.
• Bits 3 .. 0 - CS13, CS12, CS11, CS10: Clock Select Bits 3, 2, 1, and 0
The Clock Select bits 3, 2, 1, and 0 define the prescaling source of Timer/Counter1.
Table 14-2.
Bit
$30 ($50)
Read/Write
Initial value
COM1A1
CS13
0
0
1
1
0
0
0
0
0
0
0
CTC1
Comparator A Mode Select
Timer/Counter1 Prescale Select
R/W
COM1A0
7
0
0
1
0
1
CS12
0
0
0
0
1
1
1
PWM1A
R/W
6
0
Description
Timer/Counter Comparator A disconnected from output pin OC1A.
Toggle the OC1A output line.
Clear the OC1A output line.
Set the OC1A output line
COM1A1
CS11
R/W
0
0
1
1
0
0
1
5
0
COM1A0
R/W
4
0
CS10
0
1
0
1
0
1
0
CS13
R/W
3
0
Asynchronous
Clocking Mode
T/C1 stopped
PCK
PCK/2
PCK/4
PCK/8
PCK/16
PCK/32
Table 14-4 on page 90
CS12
R/W
2
0
CS11
R/W
1
0
Synchronous
Clocking Mode
T/C1 stopped
CK
CK/2
CK/4
CK/8
CK/16
CK/32
CS10
R/W
0
0
7598H–AVR–07/09
for a detailed
TCCR1