Fez Hydra Supported Features


We created a data logger using the Fez Rhino a while back and wanted to build a couple more now but the Fez Rhino has been discontinued.

So were are looking to use the Fez Hydra.

When I initially looked at the Fez Hydra soon after it was released there was mention that a number of features werent ready yet in terms of the software for the board at that stage. Looking at the product page now I dont see any mention of any of the features not being available. Can I assume that all the features listed on the product page are supported at this stage?

In particular for our data logger we require the following:

  • 4 UARTs
  • SD card support with FAT
  • Analog input
  • RTC (Realtime Clock)


Yep, Hydra has all of them.

Edit: Spoke to soon. RTC class might be missing,although all the hardware is there.

Thanks for the quick response.

Just to confirm you’re not only saying that it has the relevant hardware sockets but also that the current firmware/OS supports them all?

The reason I ask is that I seem to remember at some stage that although 4 UARTs are physically available only 1 or 2 UARTs were actually working with the firmware/OS at that stage.

I have a fairly tight deadline so I don’t want to get caught out with for example support for UARTs 3&4 will only be available in 3 months time etc.


Gus will know for sure.
The good thing is that RLP lite is there,so it is possible to add some missing functionality before the official release.

It has SPI and I2C too and in future, one wire as well.

You can do the rest using RLP or using register access. This will be good for RTC for example.

More features will be available in future but you should go by what is available now.

Is there not a Wiki page with a table listing the features with their current supported status and estimated time for support for those not currently supported?

Does that mean that everything in my list is currently supported without having to resort to using RLP?

  • 4 UARTS
  • SD card with FAT
  • Analog inputs
  • RTC

Is ‘rest’ refering to the rest of my list or the ‘rest’ of all the listed Hydra features on the product page? The reference to RTC in terms of RLP/register access implies that it isn’t currently supported from my list.

So the comments seem a bit ambiguous.


Have you checked if GHI still have the design files available for Rhino ? That way you could look to get some more made.

It was my understanding that the Hydra was released as an open source hardware / software product. That means that if it does not have a feature you want than you are free to add it and share that feature with the community. The point of open source is that everyone gets to chip in and help build up a good code base.

I know we are all spoiled by how much extra stuff, features well beyond the base NETMF libraries that GHI has added to other boards, but I don’t think we can expect GHI to do all the work on an open source project.

I’m pretty sure they are. However we’re only talking about making on the order of 2-3 data loggers so it’s not worth the effort to take the design files and get them made.

We’re happy to go with the Hydra, we’re just looking for a definitive list of what is and isn’t supported yet.


for a group of 3, I’d still consider going to dorkbotpdx and have boards made, a few orders of electronic bits including USBizi chips from GHI and a few hours with a soldering iron, done ! Especially if i didn’t want to invest in re-coding !

Hi Jeff

No problem in terms of the open source nature and chipping in, however surely there should be a fairly accurate and upto date list of what features are and aren’t supported via the Gadgeteer API?

If I go to the product page for the Hydra it has a list of all the socket types and features, UART, SD, SPI etc. and no mention that I noticed on the product page that some of them aren’t currently supported.

The only reason I even asked was because I remember seeing mention when it first came out a couple of months ago that some features weren’t supported now.

Surely the product page should clearly list which features are currently supported so people know what supported features they get when they purchase the board?


Hydra supports every single feature found standard in netmf 4.1 plus adds all features found in GHI OSH library documentation. That includes RLP lite and processor register access so you can features through compiling or through RLP.

So does that mean all 4 UARTs (sockets 4,5,6,7) are currently supported?

I can’t remember whether FAT support on SD cards was a standard netmf 4.1 feature or whether that was a GHI specific feature when we used the Fex Rhino.

So is FAT support of SD cards via socket 8 currently supported?

Ideally based on the sockets listed on the product page for the Hydra I’d like to see a table along the following lines if all them aren’t currently supported.

Socket Type Socket Numbers Status
D 2 Supported
S 3,4 Coming in Apr 2012
U 4,5,6,7 4&5 supported, 6&7 coming Mar 2012

Someone mentioned the software portion of the product was still in beta and version 1.0 hasn’t been released yet. If this is the case why is there no mention of this on the product page?


Software is complete, has all UARTs and SD file system support. The only thing that needs more tweaking is SD but this is open source product so feel free to dig into the sources.

Is there an official list of outstanding issues that require tweaking in the SD support that we can help on or do we need to look out for comments in the source code for the SD support?

No list. The driver was rushed in and not tested enough.

On the SD support issue…

I notice that if you go outside of the file size during a read that will prompt the ABORT issue :wink:

For now I’ve just decided not to be stupid and try to read outside a file’s length. But I’m silly like that.

Hi. I am helping Sean with the Data Logger project.

I just wanted to check whether there are any updates on the RTC software for the Hydra. We need the ‘BatteryRAM’ and ‘RealTimeClock’ methods that are used in the Spider. Any chance that some work in that area has been done?


You can easily get these working with register class and processor datasheet.