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Asked — Edited

I2C Thoughts...

...from the newbie... Can each digital port send I2C? Because I saw some I2C servo controllers that handle multiple servos. Could this expand the number of servos (or H-bridges) controlled?


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Synthiam
#1  

I2C allows chaining (a network) of devices. You only need one I2C interface to control 112 devices per bus.:)

That is why the EZ-B has only one I2C interface

#2  

:) Im determined to get a cybie to work with EZ-B.:) Somehow. hmmmm maybe I will think of something....Ive got a good feeling on this. It just wont be a level 1 project i think but I just KNOW this could be awesome if I can control it wireless with LAPTOP brains and new sensors.:D But alas...mobility first....

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Synthiam
#3  

Man I hope you take a lot of pics of the Cybie:)

What kind of servos are you thinking of using?

#4  

LOL there will be no evidence of the failures. Actually I bought 2 cybies. One to totally autopsy and practice on and if all goes well I would make an instructible. (Crediting DJ Sures EZ-B):) IDK about the servos. Id love to see the insides and replace those noisy gears and motors. Even if it was only a little quieter. Looking at pix on the internet I may have to keep the gear set up and put quieter motors in. Soooo...there will still be the problem of too many digital signals gobbled up for that many H-Bridges. Im still wondering if there is a ready interface solution to using a servo control pulse to create the needed HL LH LL for the H-bridge. Like ... pulses high...rotate clockwise (HL)...pulses low...rotate counter clockwise (LH)....no pulses...stop(LL).. That way only one servo port needed to control one H-Bridge. Thoughts?

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Synthiam
#5  

How many hbridges are on the i cybie?

There are 20 i/o on the ez-b...

Each motor would take 2 i/o of the ez-b (for your hh, hl, lh, ll)

You "could" look into which hbridges are ALWAYS going to be on at the same time and double up the connections, but i don't know how much that is worth to you? It'd be a lot of work to save only a few i/o

If you used 20 i/o, you deserve some sort of magical prize because that's the most anyone has used on an ez-b. i've never come close:)

#6  

There are 16 Half H bridges. For 16 motors but only 12 are for the legs. Im trying to find what that Half H circuit looks like. lol I have NO idea what Im getting into.
Prize for 20 IO? Not if its ALL H bridges because that means i really moved 10 motors and no DI/O for other stuff! -Troy

#7  

I found a tiny bit more data here. Not easy to find but OH so VERY interesting!:) Glikityclik

#8  

After I got some sleep and took a step back I thought about it more simply. Why not take a cheap servo apart for the circuitry and reassemble its controllers and potentiometers in the robot. Option 1 keep the same motors already there. Option 2 shop around for internal servo motors that just might be quieter and can use ez-b power source.

and guess what....sigh....after a few hours more digging through the internet there is a picture of EXACTLY what Im talking about.

http://www.robotshop.com/forum/showthread.php%3F795-Question-about-connexion-servo-and-motor-controller&docid=o4MZ5SWzOj2k6M&w=620&h=600&ei=4z5ZTp-5M-fE4gTal8WsBQ&zoom=1&iact=hc&vpx=758&vpy=249&dur=7450&hovh=221&hovw=228&tx=156&ty=152&page=11&tbnh=133&tbnw=137&start=225&ndsp=24&ved=1t:429,r:15,s:225&biw=1280&bih=780" target='_blank' rel="nofollow">Glikityclik