D+ and D- on different ports

General discussions about V-USB, our firmware-only implementation of a low speed USB device on Atmel's AVR microcontrollers
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D+ and D- on different ports

Post by SamFozz » Wed Jan 24, 2018 2:27 pm


I'm trying to get VUSB working on an attiny44, where INT0 is on portB, and portB has no other usable ports when an external oscillator is attached.

Would it be possible to doctor the code to support D+ and D- being on different ports? - at the moment the setting "USB_CFG_IOPORTNAME" only accepts one value.

I feel like this would not be a huge change if I knew where to look!? - any pointers would be appreciated ....

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Re: D+ and D- on different ports

Post by horo » Fri Jan 26, 2018 7:17 pm

Hi SamFozz,

I don't know if you can use different ports, but it is possible to use the pin change int instead of INT0:

Ciao, Martin

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Re: D+ and D- on different ports

Post by ulao » Fri Jan 26, 2018 7:28 pm

This should be relatively easy by adding a
and just doing a rename in the correct files and pay attention to the changes where minus and plus pins are used.

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