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Topic: Flip dot control. (Read 1 time) previous topic - next topic

KGBMike

Hello there!
Total noob here(I bet you hear that alot  :-)  )
I'm trying to get some basic ideas on how to interface with a flip dot.
I saw some topics on this forum already, but unless I'm mistaken, they deal with matrixes of the things.
I managed to get some single unit ones(from AlfaZeta) and want to start by just interfacing with one.

I'm a total noob in electronics.   However, so far I hear that you can't drive a flip-dot from an arduino pin(due to current restrictions).  So I decided to go with an H-Bridge as it can provide more current and allow me to switch polarity.
Is this a good approach?

I laid out a wiring diagram and was wondering if anyone can tell me if I'm heading in the right direction, or that of a fiery arduino death. :-)



btw...the "motor" is going to be the flipdot...for power, I'm thinking of using a 12v adapter or 9v battery fed via the power jack on the arduino.

Thanks in advance for the help!

CrossRoads

In regards to flip dot operation, yes, need a pulse of current in either direction to flip it back & forth.

As to your connections: Hard to tell without and finding a spec for the chip & see what you have hooked up.
Fritzing sucks in that regards.
Any chance you can post a real schematic?
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

KGBMike

Thanks for the quick reply!
Sorry for the layout...I'm a noob in that regard as well :-)  Just found out about Fritzing actually...didn't know what else to use(heard of Eagle though).
Anyways...here is the schematic....



In terms of flip dot opertation...their papers say I need a 1ms of 350mA of a minimum of 7.5v

Once again...thanx for the help!

dbvanhorn

For 1mS at 350mA, you're likely to need a large capacitor to supply the current.
9V batteries have a relatively high internal impedance, and it's likely that the voltage during the current pulse is sagging rather a lot.

For best results while experimenting, a bench power supply capable of 1-2A would be good, a second battery for the flipdot would work as well.  You might use AA cells in a holder for that one, and then the voltage sags would be smaller, and not cause processor resets or other weird behavior.

KGBMike

Thanks dbvanhorn.

I'll have to look into both alternatives there.
With the capacitor method...I would attach this between the Vcc and Ground, correct?  Would a 200uF(25v) be sufficient you think?

KGBMike

Also...other than the above...this h-bridge is a go?

CrossRoads

I'd say yes, just control  a burst of current one direction or the other, its supposed to stay in place once moved.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

KGBMike

Roger that!  Thanks for the help guys....I'll wire it up tomorrow possibly.

KGBMike

#8
Apr 03, 2012, 07:14 am Last Edit: Apr 04, 2012, 06:32 am by KGBMike Reason: 1
Well...it wasn't "tomorrow" but I eventually got it.
A simple blinker.  At first, I thought I didn't have enough power via usb...but it worked after all!


Makes a nice clicking noise as it flips....and best of all....no smoke, fire, or burning!

I'll upload a video soon...

KGBMike

Don't know if this is a permalink.  Let me know if its not working.

https://fbcdn-video-a.akamaihd.net/cfs-ak-ash4/452373/287/10150641562750794_43903.mp4?oh=035080510bfb59c6d22e76c9aecb3331&oe=4F7D2A00&__gda__=1333602816_137b8879fa9bb21a4d9f2937d10af409

CrossRoads

Playback on the video is terrible.
Please resize pics when you post to 800x600 kind of size, vs 3200 x 1800.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

KGBMike

#11
Apr 04, 2012, 06:28 am Last Edit: Apr 04, 2012, 06:32 am by KGBMike Reason: 1
Jeez....youre right...sorry about the giant pic....
Video plays ok here and on mobile too....should have uploaded to youtube or something...  sorry again :-)

EDIT: Pic resized!

KGBMike

Here is a youtube version of the vid:
http://www.youtube.com/watch?v=SoqYsmMevH8

CrossRoads

Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

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