Framework Fingerprint Scanner for a desktop PC?

General Topics
1

It would be very nice to have ability to login to my Linux desktop PC using a fingerprint. However, it seems there are no reasonably reliable and generally available fingerprint readers compatible with libfprint… I bought a couple on Amazon and while they work, they’re so unreliable to the point of being useless.

However, I found the fingerprint module used in the Framework Laptop 13 to be reasonably reliable (although it still fails to scan the fingerprint sometimes, and due to the generally bad fingerprint UX in Linux/KDE Plasma I then have to use my password…). And since the module is available in the Marketplace for €30, I thought it would be cool to make an external fingerprint device with it, in a 3D printed case. The reader module attaches to USB, so the main issue would be to figure out how to connect the existing connector (on a flex cable I assume) to a cable (or even better, a USB-C socket). I’m too lazy to take my Framework apart right now, but I’m going to soon and will try to figure out what connector is used and if the other part could be obtained. I have some experience with designing and ordering PCBs, so the cleanest way would be to make a small adapter PCB with a USB-C socket.

Anyway, if you have any input, please do chime in. If you have any tips on reliable external fingerprint readers for Linux, please also let me know - while this would be a cool project, I have quite a few in a pipeline already… :slight_smile:

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Standalone USB Framework Fingerprint Reader?
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There should be some information about the connector and interface on the Framework Github. I know the webcam uses standard D+/D- USB2 lanes, but the fingerprint sensor is more likely I2C or something.

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There is usb on the fingerprint header at least, if it uses that is another question. There is no i2c on the connector as far as I can see.

1 Like
Biometrics
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https://github.com/FrameworkComputer/Framework-Laptop-13/blob/main/Electrical/Pinouts.md#fingerprint-reader

The Fingerprint Reader resides on the Input Cover and connects though the Touchpad. All of its signals are directly passed to the Input Cover Interface described above. The connector used is Kyocera 046809610110846+.

Pin Signal Notes
1 VBUS 5V
2 USB_P USB data
3 USB_N USB data
4 GND
5 FPR_CTRL Output (mask switch events)
6 SWITCH Open collector output
7 FPR_LED_W
8 FPR_LED_G
9 FPR_LED_R
10 FPR_LED_COM 5V

https://www.mouser.com/c/?q=Kyocera+046809610110846
It’s a FFC Connector 0.5mm Pitch 10pos. Common enough that connectors and cables are available from aliexpress, in addition to major suppliers of course.

2 Likes
5

Thanks a lot for that, @MJ1 ! And apologies for not doing my own research first.

This means that it should be straightforward to connect the fingerprint reader itself to USB. The connectors should be relatively easy to hand-solder, too. (The RGB LED would need something to drive it, probably a MCU - but as it happens I have a few cheap a USB2 hub modules at hand that could be built into the device to connect the FPR and the MCU using a single USB cable.)

Now just to find a way to spread the shipping cost among multiple items somehow - paying €30 shipping on a €30 part wouldn’t be very economical… If anybody in the EU is looking to get anything from the Marketplace, please let me know - we could do a small “group buy” :slight_smile:

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6

Checked the datasheet. It actually uses a notched FPC/FFC cable. But I think regular non-notched cable may fit. In case that’s easier or cheaper to source in your country for prototyping.
The narrowest part at the notch of the specified cable is 5.45mm ±0.05. A non-notched Molex cable has an overall width of 5.5mm ±0.06 https://www.molex.com/pdm_docs/sd/982660098_sd.pdf

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That usually works though in most cases I tried it it is possible to misalign and short stuff so spot check with a multi-meter before plugging in.

1 Like
8

In the meantime… has anyone created a pcb that converts to regular usb yet? :excited:

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I finally started working on it. By coincidence, Framework products became available here just a couple of days ago (at last!) which should speed things up - I already ordered the fingerprint scanner module (plus some other upgrade bits - stiffer hinges and new webcam module).

The MVP would be a simple adapter PCB with a connector for the FPR FPC/FFC cable and a USB port - however, there’s also the RGW lighting around the reader (yes - red, green and white :slight_smile:) plus the switch, so I wouldn’t be happy with those not being used.

So I’d like to implement the following design:

  • 4-port USB 2.0 hub using the USB2514 chip
  • One port connected to the FPR
  • Another port connected to a RP2040 which will control the lighting and read the switch
  • 2 remaining USB 2.0 ports available on USB A sockets
  • 5 (or so) Cherry MX compatible switches (with hotswap sockets) connected to the RP2040, at least one position optionally supporting an EC11 rotary encoder; WS2812B-compatible RGB module in each switch as indicator
  • QMK/Vial firmware

BOM cost looks very reasonable. I already designed a RP2040-based controller module for custom mechanical keyboards and I’m familiar with QMK firmware, so it’s just a matter of laying out the USB hub circuit without any stupid mistakes :wink:

I’ll post a link to the KiCad project as soon as I push the initial version.

All feedback welcome!

4 Likes
10

I had the same idea to use the fingerprint scanner of the Framework laptop on a desktop and was happy to see there’s already some discussion around it. I also plan to eventually build a nice enclosure and custom PCB for it, but I decided to do some testing first.

So, I recently ordered a Framework fingerprint reader and a few FPC cables and a FPC connector breakout board from AliExpress. I finally found some time to test things today, and can report that after some initial hiccups, the fingerprint sensor works great on my desktop!

Firstly, the notched cables are definitely wider than the usual FPC cables you get. Means, the cable that came with the fingerprint reader kit doesn’t fit my breakout board, and the cables that I ordered have some wiggle room in the fingerprint reader module. Kyocera has a nice datasheet that shows a comparison between the two cable types. The notched cable has an extra 0.65 mm of width. Not ideal, but with some careful alignment, there’s enough contact.

The wiring information was extremely helpful, I only swapped the data lines at first - it seems that I needed to connect D+ on the USB-C breakout (that I still had) to D- on the fingerprint reader module (pin 3).
It was immediately recognized as a USB device after correctly wiring it, however my replacement module unfortunately didn’t have a compatible firmware (01000320 instead of the newer 01000334).

There’s been some discussion around this here:

I unsuccessfully tried various steps from the linked discussion post (fwupd on desktop, manual cab flash on desktop, manual cab flash with the module connected to my Framework 13 via USB, a Windows VM with the driver bundle on my Framework), but finally, the steps from the official update guide worked (fwupdmgr refresh --force && fwupdmgr update --force) on my Framework. It doesn’t even matter that two modules are connected at the same time (one built-in, one via USB).

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Now, the next step is building a proper enclosure.

5 Likes
[Solved] - Connect a USB-C Keyboard directly to the mainboard ribbon connector?
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Hey folks,
What is the status with this project?
Would love to have this as well :upside_down_face:

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@Maxr1998 I got as far as you did and it works :partying_face:. Did you end up creating a case?

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So far, no. I’ve been a bit lazy and the makeshift solution has been working too well for me :upside_down_face:

I wonder if we could reduce the footprint of the PCB somehow to make a really small case possible, like in the size of a single MX switch keychain.

1 Like
14

I have successfully got this to work on my Windows Desktop, after few struggles. I am using the Gen2 reader for Framework 13.

  1. I believe the pinout in Framework-Laptop-13/Fingerprint Reader at main · FrameworkComputer/Framework-Laptop-13 · GitHub is incorrect, I had to swap D+ and D- to got the device to work. The USB D- is on pin 2, and USB D+ is on pin 3.
  2. There seem to be only white LED. 5V on pin 10, GND on pin 7 and it lights up.
  3. Red or Green LEDs seems to be missing. I did not look for them much though.
  4. No idea about the push button, I do not need it, so I did not search for it.

Cheap FPC 0.5mm pitch cable and break-out board from the internet works just fine. The flex cable is bit fiddly, as the connector accepts the notched cable. Notched cable is apparently unobtanium, so the straight one must suffice. The official cable is 20cm long, so I did not consider using it.

Be sure to connect the FPC ribbon the correct side down! I spent almost hour chasing diwb weird connection, only to realize the contacts must face the PCB! Not away from it. I should have check the replacement guide first… :person_facepalming:

Windows will not automatically find the driver for the reader, it will show up in device manager as Goodix USB 2.0, but fail with error code 28 - driver not available. For me it showed up as VID_27C6&PID_609C. To get it to work, you have to download the official driver pack from Framework, available here . I chose the Intel version, but I believe it does not really matter for the reader driver.
Once you download the complete driver bundle extract from it the Goodix_Fingerprint_3.12804.0.240 directory, which contains the correct driver. Then navigate to Windows Device Manager (right click on My Computer > Manage) find the reader under Unknown/Other devices category. Right click the Goodix USB 2.0 and in properties choose to update the driver. Select update manually from files on my computer. And navigate to the unpacked directory. Windows will automatically pickup the driver and install it.
The device will change from Unknown Devices / Goodix USB 2.0 to Biometric devices / Framework Fingerprint Reader**.** No reboot was needed.

1 Like
15

Hello, is there a parts list for this project? Thank you