nrf51822 usb device

[Yoobe]

hello,

is there a way to have a usb stack/usb hid library for nrf51822? I wonder if it is possible to use rx/tx port as D-/D+ to have usb connection... or even use an external uart to usb chip like (CP2102) and programme usb device?

thanks

[Wojtek]

As far as i know, using external chip is the most recommended method.

You can see discussion here

[Yoobe]

Yes I saw this but I wanted a solution with usb hid class device and not uart.

I think there no cheap usb hid class device solution.. I am testing with a attiny85 board that use arduino with usb keyboard library..

The project: making a mechanical keyboard with BLE and USB port.

The other solution I will try : teensy 3 board with BLE board usb hid with the teensy and a ble extention for wireless device but this is not perfect as power consumption in wireless mode (teensy is not low power enough)

[Hung Bui]

@Yoobe: You can think of using a main MCU that support HID USB in combination with nRF51 as connectivity chip. The 2 chips can interface via UART/SPI. Or you can use our connectivity chip nRF8001.

[Yoobe]

Yes the main MCU could be any mbed platform or a teensy + NRF51 for ble but this will consume more power on battery I think. I wanted that nrf51822 is the main MCU for keyboard matrix, rtc, OLED lcd etc.. and add a attiny85 when the usb is connected and is off when on BLE mode. I will probably test the 2 solutions and see what is the best. Thanks