ATA5771 ATMEL Corporation, ATA5771 Datasheet - Page 118

• Manufacturer Part Number: ATA5771
• Manufacturer: ATMEL Corporation

10.4
10.4.1
10.4.2
10.4.3
66
Register Description
ATtiny24/44/84
MCUCR – MCU Control Register
PORTA – Port A Data Register
DDRA – Port A Data Direction Register
Table 10-9.
1.
2.
• 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 54
Bit
Read/Write
Initial Value
Bit
0x1B (0x3B)
Read/Write
Initial Value
Bit
0x1A (0x3A)
Read/Write
Initial Value
Signal
Name
PUOE
PUOV
DDOE
DDOV
PVOE
PVOV
PTOE
DIEOE
DIEOV
DI
AIO
EXT_OSC = crystal oscillator or low frequency crystal oscillator is selected as system clock.
EXT_CLOCK = external clock is selected as system clock.
PB1/XTAL2/PCINT9
EXT_OSC
0
EXT_OSC
0
EXT_OSC
0
0
EXT_OSC
PCINT9 • PCIE1
EXT_OSC
PCINT9 Input
XTAL2
PORTA7
BODS
Overriding Signals for Alternate Functions in PB1..PB0
R/W
DDA7
R/W
R/W
7
0
7
0
7
0
(1)
(1)
(1)
(1)
(1)
PORTA6
+
• PCINT9 • PCIE1
DDA6
PUD
R/W
R/W
R/W
6
0
6
0
6
0
for more details about this feature.
PORTA5
DDA5
R/W
R/W
R/W
5
0
5
0
SE
5
0
PORTA4
DDA4
R/W
R/W
4
0
4
0
SM1
R/W
4
0
PB0/XTAL1/PCINT8
EXT_CLOCK
0
EXT_CLOCK
0
EXT_CLOCK
0
EXT_CLOCK
(PCINT8 • PCIE1)
( EXT_CLOCK
(EXT_CLOCK
XTAL1
0
CLOCK/PCINT8 Input
PORTA3
DDA3
R/W
R/W
3
0
3
0
SM0
R/W
3
0
(2)
(2)
(2)
(2)
(2)
(2)
PORTA2
DDA2
+ EXT_OSC
+ EXT_OSC
+ EXT_OSC
+ EXT_OSC
BODSE
R/W
R/W
• EXT_OSC
• PWR_DOWN ) +
2
0
2
0
R/W
2
0
PORTA1
DDA1
R/W
ISC01
R/W
1
0
1
0
(1)
(1)
(1)
(1)
R
1
0
(1)
+
• PCINT8 • PCIE1)
PORTA0
DDA0
ISC00
R/W
R/W
R
0
0
0
0
0
0
8006G–AVR–01/08
MCUCR
PORTA
DDRB
“Con-