Datasheet

18.4.1 SFIOR – Special Function IO Register

Name: SFIOR

Offset: 0x30 [ID-00000142]

Reset: 0

Property: When addressing I/O Registers as data space the offset address is 0x50

When using the I/O specific commands IN and OUT, the I/O addresses 0x00 - 0x3F must be used. When

addressing I/O Registers as data space using LD and ST instructions, 0x20 must be added to these offset

addresses.

Bit 7 6 5 4 3 2 1 0

PUD

Access

R/W

Reset 0

Bit 2 – 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 Configuring the Pin for

more details about this feature.

AVR 8-Bit Microcontroller

I/O Ports

Datasheet Complete

40001974A-page 94