Elgato CAM LINK 4K

This PCB is relevant to the project because AXIOM Beta generates HDMI content inside its Beta Main Board FPGA and therefore almost any data can be sent over an HDMI connection. This provides a potential solution to not having control at the HDMI receiver side (recorder manufacturers do all kinds of strange things with the image, e.g. sharpening, colour conversions, etc... and in general only support very specific resolutions/frame-rates. Coincidentally there are also no standards for HDMI.

With the Elgato CAM Link 4k it could now become possible to take over control of the receiver side. This opens up a whole world of possibilities with regards to what data could be packed into the HDMI "frame" if it were to be used as a data container.

The device can be purchased from here

1 PCB

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  PCB Side 1.

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  PCB Side 2 (mirrored).

It is reported to be an 8 layer PCB. Probably atleast a 2-3+ HDI.

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  PCB Side View

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  PCB Layer 1/8

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  PCB Layer 2/8

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  PCB Layer 3/8

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  PCB Layer 4/8 (Now from the back, flipped for ease of alignment.) Another solid ground plane.

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  PCB Layer 5/8 (flipped) Power planes.

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  PCB Layer 6/8 (flipped) Two sneaky DDR memory pairs routed on this layer.

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  PCB Layer 7/8 (flipped) ground plane - Note: 2 cutouts in this plane, that seem to correspond to SW signals of DCDC buck converters. I've never seen that before? Maybe to reduce capacitance on the SW pin?

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  PCB Layer 8/8 (flipped) bottom layer

Pinout Mapping (WIP):

• https://docs.google.com/spreadsheets/d/17SmOY7Npzz2Hj1kz4DWKzrBAl0PYMWU085NeT3AY0D4/edit#gid=0

2 Firmware

a dump of the SPI communication (and the decoded flash data) can be found here:

• http://vserver.13thfloor.at/Stuff/ELGATO/boot_decode.txt
• http://vserver.13thfloor.at/Stuff/ELGATO/boot.vcd.xz

3 Further files/links

• http://vserver.13thfloor.at/Stuff/ELGATO/
• https://github.com/ktemkin/camlink-re

4 Credits

• https://twitter.com/GregDavill