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7 program example, 3 alternate port functions, Alternate port – Rainbow Electronics ATtiny10 User Manual

Page 45: Refer to the individual module sectio

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45

8127B–AVR–08/09

ATtiny4/5/9/10

10.2.7

Program Example

The following code example shows how to set port B pin 0 high, pin 1 low, and define the port
pins from 2 to 3 as input with a pull-up assigned to port pin 2. The resulting pin values are read
back again, but as previously discussed, a nop instruction is included to be able to read back the
value recently assigned to some of the pins.

Note:

See

“Code Examples” on page 5

.

10.3

Alternate Port Functions

Most port pins have alternate functions in addition to being general digital I/Os. In

Figure 10-6

below is shown how the port pin control signals from the simplified

Figure 10-2 on page 41

can

be overridden by alternate functions.

Assembly Code Example

...

; Define pull-ups and set outputs high

; Define directions for port pins

ldi

r16,(1<

ldi

r17,(1<

ldi

r18,(1<

out

PUEB,r16

out

PORTB,r17

out

DDRB,r18

; Insert nop for synchronization

nop

; Read port pins

in

r16,PINB

...