USB pins: INPUT or OUTPUT?

[TheDude]

Hi all,

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DDRD = ~(1 << 2);   /* all outputs except PD2 = INT0 */
DDRB = ~USBMASK;    /* set all pins as outputs except USB */

form the PowerSwitch example project
so USB is input

Code: Select all

DDRD = 7;    /* 0000 0111 bin: all pins input except USB (-> USB reset) */

from HIDKeys example project
so USB is output

what now, input or output?



thx

[Daid]

Both. The USB pins are bi-directional. I think the USB code configures them anyhow, for bi-directional ports you need to change both the DDR and PORT register.