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Alternate functions for port d, Port d schematics – Rainbow Electronics AT90S1200 User Manual

Page 35

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35

AT90S1200

0838H–AVR–03/02

Note:

n: 6…0, pin number.

Alternate Functions for Port D

The alternate functions of Port D are:

• T0 – Port D, Bit 4

T0, Timer/Counter0 clock source. See the timer description for further details.

• INT0 – Port D, Bit 2

INT0, External Interrupt source 0. See the interrupt description for further details.

Port D Schematics

Note that all port pins are synchronized. The synchronization latches are, however, not
shown in the figures.

Figure 27. Port D Schematic Diagram (Pins PD0, PD1, PD3, PD5, and PD6)

Table 11. DDDn Bits’ Effect on Port D Pins

DDDn

PORTDn

I/O

Pull-up

Comment

0

0

Input

No

Tri-state (High-Z)

0

1

Input

Yes

PDn will source current if ext. pulled low.

1

0

Output

No

Push-pull Zero Output

1

1

Output

No

Push-pull One Output