OpenSK_USB/docs/hardware.md

Overview

We have two types of OpenSK, V1 and V2. They have almost same schematic but different casing.
Currently only V2 is available to the market.

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OpenSK V2

It has a metal housing with only one button in the aft area.

!!! note "NOTE" The LED and User button are together. The button material is transparent, so user can see LED light through the button.

1. Switch To bootloader mode

After user connects the device to computer, push and hold on the user button for more than 8 seconds and then release the button. If the red LED is breathing, OpenSK is in bootloader mode.

2. LED status

LED behaviour	Mode type	Triger Method
Red LED is breathing	bootloader mode	Connect OpenSK to USB port, press the user button for more than 8 seconds and then release the button
Red LED is flashing	bootloader mode	Flash the firmware
No LED on	Working mode	Idle
R/G/B LED is flashing	Working mode	Wait for user presence when receiving FIDO command

3. Hardware

The hardawre schematic and PCB are shared here.

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OpenSK V1

It has a 3D-printed case with one user button and one RESET button.

1. Switch To bootloader mode

After connect OpenSK to USB port, please insert a paper clip or a SIM-eject tool to the RESET button hole to switch it to bootloader mode. This is similar as user pushes the RESET button on original nRF52840 USB dongle.

!!! note "NOTE" RESET button hole is covered by OpenSK label. So if you want to program the firmware occasionally, you can choose not to cover the label although we send the label to you together with OpenSK hardware.

2. LED status

LED behaviour	Mode type	Triger Method
Blue LED is breathing	bootloader mode	Use a paper clip or a SIM-eject tool to push RESET button in RESET button hole
Blue LED is flashing	bootloader mode	Flashing the firmware
No LED on	Working mode	Idle
R/G/B LED is flashing	Working mode	Wait for user presence when receiving FIDO command

3. Hardware

The hardawre schematic and PCB files can be downloaded here.