ATTINY25-20SUR Atmel, ATTINY25-20SUR Datasheet - Page 66

• Manufacturer Part Number: ATTINY25-20SUR
• Description: MCU AVR 2KB FLASH 20MHZ 8SOIC
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY25-20SUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 6
• 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 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10.4
10.4.1
10.4.2
10.4.3
10.4.4
66
Register Description
ATtiny25/45/85
MCUCR – MCU Control Register
PORTB – Port B Data Register
DDRB – Port B Data Direction Register
PINB – Port B Input Pins Address
• Bit 6 – PUD: Pull-up Disable
When this bit is written to one, the pull-ups in the I/O ports are disabled even if the DDxn and
PORTxn Registers are configured to enable the pull-ups ({DDxn, PORTxn} = 0b01). See
figuring the Pin” on page 56
Bit
0x35
Read/Write
Initial Value
Bit
0x18
Read/Write
Initial Value
Bit
0x17
Read/Write
Initial Value
Bit
0x16
Read/Write
Initial Value
BODS
R
7
0
R
R
R
7
–
0
7
–
0
7
–
0
PUD
R/W
R
R
R
6
0
6
–
0
6
–
0
6
–
0
for more details about this feature.
PORTB5
PINB5
DDB5
R/W
R/W
R/W
N/A
R/W
5
0
5
0
SE
5
5
0
PORTB4
DDB4
PINB4
R/W
R/W
R/W
N/A
4
0
4
0
4
SM1
R/W
4
0
PORTB3
PINB3
DDB3
R/W
R/W
R/W
N/A
3
0
3
0
3
SM0
R/W
3
0
PORTB2
PINB2
DDB2
R/W
R/W
BODSE
R/W
N/A
2
0
2
0
2
R
2
0
PORTB1
DDB1
PINB1
R/W
R/W
R/W
ISC01
N/A
R/W
1
0
1
0
1
1
0
PORTB0
PINB0
DDB0
ISC00
R/W
R/W
R/W
R/W
N/A
0
0
0
0
0
0
0
2586M–AVR–07/10
MCUCR
PORTB
DDRB
PINB
“Con-