AT43USB355M-AC ATMEL [ATMEL Corporation], AT43USB355M-AC Datasheet - Page 71

• Manufacturer Part Number: AT43USB355M-AC
• Description: Full-speed USB Microcontroller with Embedded Hub, ADC and PWM
• Manufacturer: ATMEL [ATMEL Corporation]

PortD as General
Digital I/O
2603G–USB–04/06
PDn, General I/O Pin: The DDDn bit in the DDRD register selects the direction of this pin. If
DDDn is set (one), PDn is con-figured as an output pin. If DDDn is cleared (zero), PDn is con-
figured as an input pin. If PORTDn is set (one) when the pin is configured as an input pin, the
MOS pull-up resistor is activated. To switch the pull-up resistor off, the PORTDn has to be
cleared (zero) or the pin has to configured as an output pin. The Port D pins are tri-stated
when a reset condition becomes active, even if the clock is not active.
Table 28. DDDn Bits on Port D Pins
Note:
DDDn
0
0
1
1
n: 7, 6...0, pin number.
PORTDn
0
1
0
1
Output
Output
Input
Input
I/O
Comment
Tri-state (Hi-Z)
PDn will source current if ext. pulled low.
Push-Pull Zero Output
Push-Pull One Output
AT43USB355
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