Datasheet

91
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
Register description
14.3.5 MCUCR – MCU Control Register
Note: 1. Only available in the Atmel ATmega164PA/324PA/644PA/1284P.
• Bit 4 – 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 ”Con-
figuring the Pin” on page 73 for more details about this feature.
14.3.6 PORTA – Port A Data Register
14.3.7 DDRA – Port A Data Direction Register
14.3.8 PINA – Port A Input Pins Address
14.3.9 PORTB – Port B Data Register
14.3.10 DDRB – Port B Data Direction Register
14.3.11 PINB – Port B Input Pins Address
Bit 7 6 5 4 3 2 1 0
0x35 (0x55)
JTD BODS
(1)
BODSE
(1)
PUD – – IVSEL IVCE MCUCR
Read/Write R/W R/W R/W R/W R R R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 76543210
0x02 (0x22)
PORTA7 PORTA6 PORTA5 PORTA4 PORTA3 PORTA2 PORTA1 PORTA0
PORTA
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value00000000
Bit 76543210
0x01 (0x21) DDA7 DDA6 DDA5 DDA4 DDA3 DDA2 DDA1 DDA0 DDRA
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value00000000
Bit 76543210
0x00 (0x20) PINA7 PINA6 PINA5 PINA4 PINA3 PINA2 PINA1 PINA0 PINA
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value N/A N/A N/A N/A N/A N/A N/A N/A
Bit 76543210
0x05 (0x25)
PORTB7 PORTB6 PORTB5 PORTB4 PORTB3 PORTB2 PORTB1 PORTB0 PORTB
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value00000000
Bit 76543210
0x04 (0x24) DDB7 DDB6 DDB5 DDB4 DDB3 DDB2 DDB1 DDB0 DDRB
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value00000000
Bit 76543210
0x03 (0x23) PINB7 PINB6 PINB5 PINB4 PINB3 PINB2 PINB1 PINB0 PINB
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value N/A N/A N/A N/A N/A N/A N/A N/A