FEZ Lemur user manual & details

Hi guys,

I own a Panda II since a while and I am very interested by either the Panda III, or a smaller and less expensive Lemur. I’m trying to stretch the price for a commercial project involving .NET micro framework boards as masters, plus many slaves either as other GHI boards or smallers Arduino Pro Mini connected using SPI and/or I2C.

But unlike the Panda, I can barely find information, examples and data related to the Lemur. Is there some user manual, review, whatever somewhere that I missed specifically for it, to complement the specs from GHI website? I didn’t even found a proper Pin Out description, except looking at photos of the board itself.

One specific question if you don’t mind. The specs says that it needs 5V only as a input. How much precisely 5V? Can a cheap voltage regulator board using a L7805 would be okay?
http://www.datasheets360.com/pdf/5892024673594838244?query=L7805
My project will be powered by “unknown” kind of voltage by users, typically MiMh cells but could be whatever. So a component like the L7805 is appealing, to be able to get a large range of input, AC or DC and a regulated 5V out. Some cheap chinese power supply build around L7805 are available for a couple bucks. Would they be adequate to power the Lemur?

Thanks for your advices!

Daniel.

@ DanielM - That regulated power should be sufficient.

The regulated power needs to maintain 5V for the 5V output on the header for external circuitry and the regulated power input should NOT exceed 5V or it could damage the board.

@ DanielM - There is no dedicated user manual for the FEZ Lemur. You can find more information in the G30 manual, the FEZ Lemur schematic, and GHI.Pins.FEZLemur in the GHI.Pins assembly in our SDK.

Thanks guys! I will look into the G30 documentation. Any particular reason why there’s no manual? I would hate to pick a board that become obsolete or fade out. :slight_smile:

it’s a G30 at the heart of it - not new, but certainly not old. I’d be surprised if it was something that GHI had any thoughts about replacing at this point. That’s also the reason there’s no manual - it’s a G30, all you need are the pin definitions that your board exposes plus the generic G30 manual and you’re good to go.

@ DanielM - sorry this wasn’t clear. There is a manual, which is a combination of the G30 datasheet (the heart of the panda) and the netmf manual pdf, covering all devices.

Instead of having many repeated manuals, we unify all in a simpler document.

There are no current plan to discontinue the G30 or the panda. They are new and popular products.

@ Gus - Thanks for the clarification Gus! Lemur/G30 seems to fit my bill and needs. In fact, now I undestand that the G30 TH Module could fit my bill just as well. I don’t really need the arduino form factor as the thing is intended to be potted in resin anyway :slight_smile:
Need more studies… and tests…

One thing I have noticed when trying to gather information about the Spider 2 kit is that GHI has included links to the individual products in the product description. Likewise for the individual (main board) product there is a link to the chip/module used on that board. After I realized this it became very easy to find the information I needed.

Another thing I had to remind myself of is that it really is F’ing Easy. I was looking for example code for the TE35 and then realized that it is NETMF and FEZ so all the GHI displays work about the same, I could use the code in the .NET ‘Gadgeteer for Beginners’ with my display even though the book shows using the N18.

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@ Aron - I have had a look at the Fez Lemur circuit diagram and it looks like the 5V rail is only used on the 6 pin header (pin 4) and JP2 (pin 20) for powering external hardware.

I’m looking at using a Fez lemur to replace a devDuino as the controller on my electric longboard and the ESC for the motor has a 6VDC output which I would like to use for power. (Normally this is used to power RC receiver)

Assuming that I’m not going to power anything off the 5V rail would this be ok?

@ KiwiBryn
blog.devmobile.co.nz

5v is not intended to be an input at more than USB voltage. It is the input into the 3v3 regulator - a higher input voltage can cause more heat from that reg. The USB power line is protected by a diode.

So in theory you could - but I’d say ESCs are notoriously known for unclean power output, you really might want to think about trying to find a low dropout voltage switching regulator module (maybe one of these? http://www.ebay.com.au/itm/400932034935?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT) and you might have more protection with that.