Need help to build the fez-hydra PK

I am new to gadgeteer and I am getting a lot of errors when building the hydra pk.
Here are my env and tools:

  • Using GCC 4.9.3 (GNU Tools ARM Embedded)
  • Using VS 2013 tools
  • Using the fez-hydra PK from ghi’s git repo

Building the top level build.dirproj gave me lots of errors, building the solution\fez-hydra subsequently gave lots of errors too.

The fez-hydra is open source right ? So there must be lots of people already building this pk/firmware successfully I think, but what I am not sure is if the gcc toolchain is actually supported.

Has anyone successfully build the hydra PK using gcc toolchain ? I would like to hear from you. Thanks!

No, I suspect your assumption is incorrect. GHI build the firmware for the Hydra and bundle it in their SDK. Most people are leveraging that.

@ puresoul - You might try the document below, I wrote this up when I was doing a custom firmware build for earlier versions of the hydra firmware.

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Great, thanks for the pointer. I will look into this - though I intend to port it to the 4.3.1 base, so additional changes are most likely needed.

Btw, I have successfully built the pk for netduino+2, so now have some confidence in doing this :slight_smile:

Hmm really ?
I thought it was mentioned explicitly in the hydra page that it’s an open source, plus there are pk codes in the ghi git for hydra.

I really would like to hear anyone from GHI to confirm the open-source status of hydra.


I think this document states the open-source status of the Hydra:

@ puresoul - The Hydra is under the same open source license it always has been. You can find it’s source at We keep the entire porting kit up there now and not just a diff.

We will be getting an updated guide released in the future that will walk you through building the firmware with GCC step by step. There are some build issues we need to fix before then though. No promises on when though.

@ Mike beat me to it, I apologize for missing the original post.

@ puresoul - most people use the firmware as is and change the board, however there have been a few people who built their own firmware.

and @ John types faster than I do…lol ;D

@ Gary -

Thanks for the reply and the confirmation on the open source status.

I am glad to see the gadgeteering community in GHI is really active and alive. :slight_smile:

This makes me leaning to ghi for getting future netmf devices.

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@ John -

Thanks! I really look forward to the gcc toolchain instructions.

Btw, which toolchain has been officially used for building the hydra ? Keil or RVDS ?
Both are way way out of my budget ^^.

Supporting gcc in the Hydra PK would be great for hobbyists and home/personal projects as Keil/RVDS is just too prohibitively expensive. I think this will help spread the popularity of the ghi platforms.

@ puresoul - We use RVDS internally. GCC at one point worked for Hydra but over the past few years it hasn’t been kept up to date. We will be making sure that GCC works for Hydra soon.

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Since its open source, could someone put that new cpu on it that’s energy efficient or something?

@ MRTFEREN - what is wrong with the one it has now?

To be crystal clear, because I was not earlier, your assumption that there are many others out there building hydra firmware with gcc is flawed. You can, people do, but you’re not going to find many who have. Your assertion that hydra is open source is spot on as others have noted.