Attiny84 Keyboard

[Soumojit28]

Can you help me how can I use this with attiny84 to act as a keyboard?

[zaher]

follow this project it is based on another one with improvements, it is IR project but you can modify it to send keyboards

https://github.com/parmaja/usbIRConsumer

[Soumojit28]

Thanks for the quick answer, I have some more questions as I am using an attiny84 is it require an external 16Mhz crystal to communicate with the usb? and need a bit more help with the schematics, which pins on attiny84 should connect to usb?

[zaher]

look at this project https://nathan.chantrell.net/20121014/tinypcremote-an-attiny85-based-infrared-pc-remote-control/
you can remove the part of IR reciever, and keep attiny send keyboard message by adding push button for example

[Soumojit28]

Yup, I sawed it, but the thing is will this stays the same for an attiny84, and any ideas if I need an external crystal for it?

[zaher]

just add it, look at this schema, i used external crustal 20 for my project

https://www.avrfreaks.net/forum/implement-usb-device-attiny85

[Soumojit28]

So tried it, added a 16Mhz crystal in attiny84, its working with the crystal, modified the usbconfig.h like this

``/* This is the port where the USB bus is connected. When you configure it to

• "B", the registers PORTB, PINB and DDRB will be used.
  /
  #define USB_CFG_DMINUS_BIT 1
  / This is the bit number in USB_CFG_IOPORT where the USB D- line is connected.
• This may be any bit in the port.
  /
  #define USB_CFG_DPLUS_BIT 2
  / This is the bit number in USB_CFG_IOPORT where the USB D+ line is connected.
• This may be any bit in the port. Please note that D+ must also be connected
• to interrupt pin INT0! [You can also use other interrupts, see section
• "Optional MCU Description" below, or you can connect D- to the interrupt, as
• it is required if you use the USB_COUNT_SOF feature. If you use D- for the
• interrupt, the USB interrupt will also be triggered at Start-Of-Frame
• markers every millisecond.]
  */
  #define USB_CFG_CLOCK_KHZ 16000``

Compiled the example sketch in the library and uploaded the code but getting Unknown USB Device (Device Descriptor Failed) in the device manager. any ideas whats wrong here?

[zaher]

I can not help you, because it is not my main job, it is just hobby project.