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CDC - Conneting a Fez to another Fez?


#1

Hello All,

Given the nature of the CDC client device in 4.1 doesn’t that now mean that we can connect A fez domino to another Fez Domino via USB?!

Then theoritically you could make a token ring network or a star network with a hub? Then so long as you can power it you could connect 255 Fez Dominos together… Am I right?


#2

You can connect 128 Dominos all together on a USB network…the 128 is the USB limitation by design…but why would you want to do that? It would be fun as a video demonstration but not very useful


#3

128 devices on the bus right. But that is for a host port right? I.e. 128 devices can connect each domino’s host port.

As for practically (other than making a good video) It could be used as a good educational tool to teach students how to develop distrubuted applications for enterprise systems.

Who knows, if you chain enough together you might even be able to run the TinyClr.com website off of it, just to show off GHI’s Technical Superiority :smiley:


#4

Oh yes that is 128 per domino! so you can have unlimited dominos connected!


#5

This is a smart idea kurtnelle.


#6

So then if we write an application that creates a “slave” Fez Domino then we’ll have 8 com ports, 10 PWM 2 analog in etc to work with in addition to more compute power? One might require multiple computers to debug the entire system at the same time though.

What is the max data rate of the Usbizi’s CDC? Is it about 1Mbps?


#7

I think CDC can get you about 200K bytes/sec


#8

This sounds cool! Would be a great way of creating an array of FEZ :o


#9

As long as this concept is limited to “I know it is a bad idea, but why not?” you could probably do all sorts of things like self replicating code and such. Maybe you could write a “virus” to infect the other Dominos in the array.

Still though, why not just network them together with Ethernet?


#10

Or with Xbee?


#11

Xbee, Ethernet, serial, SPI, all of those would work. I still want to know, though, why do it in the first place? More IO? Why not just connect them by serial at a fast baud rate then?


#12

The USB will allow you to connect to another fez’s and other usb devices at the same time (with a hub) such as mass storage, and game controllers, whereas serial isn’t as flexible. But this that would just be a technology demonstration; not a serious solution (unless you’re harvesting the compute power). Also usb connectivity is as simple as one cable to another, whereas Serial is at least 2, and Ethernet requires more hardware.

This is about ideas to squeeze as much functionality out of that tiny chip as possible :slight_smile: