Which Gadgeteer Board?

Time for a break from the motors and ESC research into something more comfortable :)

The Options

There's a few manufacturers I found doing Gadgeteer Mainboards, namely: GHI Electronics, Love Electronics and Sytech Electronics.

What distinguishes the boards are three factors: Processing Power, Memory and Connectivity to other Gadgeteer modules (i.e. sensors, switches, etc).

There is of course the cost.  These boards are a bit of money but nothing prohibitively expensive, so I'll ignore the cost and buy the best one for me.

BTW, there are quite a few companies creating Gadgeteer modules and they are all meant to work with any mainboard.

So what are the best offerings from these companies:

• GHI's FEZ Spider = $120 (USD) ~ £75
• Love's Argon R1 = £70
• Sytech's Nano = £70

They are all lovely boards.  For me, I'm going for the Love Electronics product.  Why?

Speed

The Spider and Nano runs at 200MHz where the Argon R1 is 120MHz, it's down on power yet that's not everything.

The drone will have an autopilot program that will be complex to write however I believe the number crunching won't be too heavy.

It is only basic simple Newton motion mathematics.  I'm not decompressing video or calculating molecule interactions.

120MHz will be great for my drone :)  Fingers crossed!

FYI, it's still so hard to understand how much "real" processing you'll get per MHz.  All the above buy their chips from NXP who implement the ARM processor version 7.  I dug around a bit, found out loads on each boards processor (won't bore you) however ultimately you never know ... will be run trying :)

Memory

This is where the Love Electronic's product wins.  FYI, there are two types of memory: RAM for your processor as a temporary storage and Flash for storage after power down.

• Nano has 8MB of RAM and 8MB of Flash
• Spider has 16MB of RAM and 4.5MB of Flash
• Argon R1 has 32MB of RAM and 128MB of Flash

OK, with the Nano and Spider I could get an SD memory card and write data to that.  That's a pain, more coding and another connector taken for the SD card module.

Even if I could be bothered, the Argon R1 still has double the RAM.  I like the sound of that.

My program might not need mega data processing however I'm always surprised how much RAM one needs. Better safe than sorry. Thank you Love Electronics!

Connectors

In terms of connectors, the drone will need many for all the sensors.  As this is my fun time R&D project I don't know how many sensors I need.

At worst I'll need to put multiple sensors on each of the Quadcopter's arms ... that's 4x gyroscopes, 4x accelerometer and a GPS. Plus it will need wireless comms to get the beckon's GPS location.  That's a lot of sensors!

Also a kill button would be important for safely plus later the ultrasonics for landing.

Ummm, I need a lot of connectors and none of the boards have enough.  I will have to think of a clever way around however for now best to get as many connectors as possible.

What I found on connectors:

• Nano is a little low on Gadgeteer connectors at 10 connectors
• Both Love Electronics and GHI has 14 each and I believe with the same distribution of interfaces.

Summary

The race was between GHI's Spider and Love Electronics' Argon R1, sorry Nano.

The Spider probably has more processing grunt however the Argon R1 has double the RAM and over 28x more Flash memory.

The only extra on GHI is the "Premium" pack.  It allow you to do some low level programming however I really can't see myself wanting to do that :)

Yes for me with all that memory, Love Electronics has it with the Argon R1 ... sorry if I was RAMing the message home :)