ATtiny85 Atmel Corporation, ATtiny85 Datasheet - Page 47
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ATtiny85
Manufacturer Part Number
ATtiny85
Description
Manufacturer
Atmel Corporation
Datasheets
1.ATTINY25.pdf
(34 pages)
2.ATTINY25.pdf
(34 pages)
3.ATTINY25.pdf
(30 pages)
4.ATTINY85.pdf
(234 pages)
Specifications of ATtiny85
Flash (kbytes)
8 Kbytes
Pin Count
8
Max. Operating Frequency
20 MHz
Cpu
8-bit AVR
# Of Touch Channels
3
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)
0.5
Eeprom (bytes)
512
Self Program Memory
YES
Dram Memory
No
Nand Interface
No
Picopower
No
Temp. Range (deg C)
-40 to 85
I/o Supply Class
1.8 to 5.5
Operating Voltage (vcc)
1.8 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
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
ATtiny85-15SZ
Manufacturer:
ATMEL
Quantity:
30
Company:
Part Number:
ATtiny85-20PU
Manufacturer:
CUI
Quantity:
1 000
Part Number:
ATtiny85-20SU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
Company:
Part Number:
ATtiny85V-10SH
Manufacturer:
Intel
Quantity:
62
Part Number:
ATtiny85V-10SU
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
8.5.2
2586N–AVR–04/11
WDTCR – Watchdog Timer Control Register
• Bit 3 – WDRF: Watchdog Reset Flag
This bit is set if a Watchdog Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 2 – BORF: Brown-out Reset Flag
This bit is set if a Brown-out Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 1 – EXTRF: External Reset Flag
This bit is set if an External Reset occurs. The bit is reset by a Power-on Reset, or by writing a
logic zero to the flag.
• Bit 0 – PORF: Power-on Reset Flag
This bit is set if a Power-on Reset occurs. The bit is reset only by writing a logic zero to the flag.
To make use of the Reset Flags to identify a reset condition, the user should read and then reset
the MCUSR as early as possible in the program. If the register is cleared before another reset
occurs, the source of the reset can be found by examining the Reset Flags.
• Bit 7 – WDIF: Watchdog Timeout Interrupt Flag
This bit is set when a time-out occurs in the Watchdog Timer and the Watchdog Timer is config-
ured for interrupt. WDIF is cleared by hardware when executing the corresponding interrupt
handling vector. Alternatively, WDIF is cleared by writing a logic one to the flag. When the I-bit in
SREG and WDIE are set, the Watchdog Time-out Interrupt is executed.
• Bit 6 – WDIE: Watchdog Timeout Interrupt Enable
When this bit is written to one, WDE is cleared, and the I-bit in the Status Register is set, the
Watchdog Time-out Interrupt is enabled. In this mode the corresponding interrupt is executed
instead of a reset if a timeout in the Watchdog Timer occurs.
If WDE is set, WDIE is automatically cleared by hardware when a time-out occurs. This is useful
for keeping the Watchdog Reset security while using the interrupt. After the WDIE bit is cleared,
the next time-out will generate a reset. To avoid the Watchdog Reset, WDIE must be set after
each interrupt.
Table 8-2.
Bit
0x21
Read/Write
Initial Value
WDE
0
0
1
1
Watchdog Timer Configuration
WDIF
WDIE
R/W
7
0
0
1
0
1
WDIE
R/W
6
0
Watchdog Timer State
Stopped
Running
Running
Running
WDP3
R/W
5
0
WDCE
R/W
4
0
WDE
R/W
X
3
WDP2
R/W
2
0
Action on Time-out
None
Interrupt
Reset
Interrupt
ATtiny25/45/85
WDP1
R/W
1
0
WDP0
R/W
0
0
WDTCR
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