Show Posts
Pages: 1 ... 8 9 [10] 11
136  Forum 2005-2010 (read only) / Interfacing / Re: Q: arduino 7sement clock? on: July 23, 2009, 04:15:24 pm
ok wow.

thank you for all the advice, I am looking forward to digging in. I'll report how it worked when the parts get here in 10 days

fubbi
137  Forum 2005-2010 (read only) / Interfacing / Re: Q: arduino 7sement clock? on: July 20, 2009, 05:51:09 am
Sounds like a challenge to me  smiley-wink

so I should either
a. find a 12v chip
b. find a big 5v seven seg
c. figure out how to pipe in the extra juice

I have done a few projects along the lines of the "driving bigger loads" tutorial, using transistors or mosfets. would this be different?

fubbi
138  Forum 2005-2010 (read only) / Interfacing / Re: Q: arduino 7sement clock? on: July 19, 2009, 11:37:56 am
wow, nice chip!

the shop i found (http://spezial.com)has three options and no info, pl+?, wl+?:

austriamicrosystems / AS1107PL+
8-Digit Common-Cathode LED Display Driver
2.7V-5.5V/1mA*10µA SHDN*SPI Interface

austriamicrosystems / AS1107WL+
8-Digit Common-Cathode LED Display Driver
2.7V-5.5V/1mA*10µA SHDN*SPI Interface

austriamicrosystems / AS1107WL+T
8-Digit Common-Cathode LED Display Driver
2.7V-5.5V/1mA*10µA SHDN*SPI Interface
139  Forum 2005-2010 (read only) / Interfacing / Re: Q: arduino 7sement clock? on: July 19, 2009, 10:26:48 am
ok got it! I found the mentioned post. looked very useful

thanks everybody
140  Forum 2005-2010 (read only) / Interfacing / Re: Q: arduino 7sement clock? on: July 18, 2009, 02:51:02 pm
hey
I hear ya, they are big (love it!). but it's for an art installation in public.

Thanks for the tip with the high power units - I was wondering about that. Am I right to assume that i need one per segment? I never worked with shift registers but i will figure it out. just need to know what to buy...

And using the RTC makes sense right?


fubbi
141  Forum 2005-2010 (read only) / Interfacing / Q: arduino 7sement clock? on: July 18, 2009, 12:21:39 pm
hello

I am reading up on all the various articles about creating a LED display clock with the arduino.

Does this combination (or equivalent) sound right?

arduino pro mini      http://www.sparkfun.com/commerce/product_info.php?products_id=9218
7-Segment Red 6.5" http://www.sparkfun.com/commerce/product_info.php?products_id=8530
RTC module http://www.sparkfun.com/commerce/product_info.php?products_id=99
shift regs http://www.sparkfun.com/commerce/product_info.php?products_id=733

The RTC would supply the arduino with the current time and I use one shift register per module.
is this the way to go about it?

thank you

fubbi
142  Forum 2005-2010 (read only) / Interfacing / Re: Controlling 120v Lights on: December 04, 2008, 08:52:30 am
I am using this:
http://www.vellemanprojects.com/ot/en/product/view/?id=354314

143  Forum 2005-2010 (read only) / Interfacing / Re: ping to AC - scaling values on: December 04, 2008, 06:46:05 am
brilliant! just what i was looking for

thank you everybody
144  Forum 2005-2010 (read only) / Interfacing / Re: ping to AC - scaling values on: December 04, 2008, 06:20:58 am
Quote
or you can just do this:
 val = map(200,13000, 0,255)

that sounds very useful, but will that really scale everything inbetween too, or just those hard values?

thank you

fubbi




145  Forum 2005-2010 (read only) / Interfacing / Re: ping to AC - scaling values on: December 03, 2008, 06:38:04 pm
thank you for your speedy gonzales reply!

Quote
Quote:
i will control the dimmer with an analogue PWM value right?

Well no not directly. The PWM output needs to be boosted to 12V using a transistor. Then it needs to be smoothed using a series resistor, and a capacitor and then it can be applied to your controller.

The dimmer manual says "Use an adjustment voltage of 0 to 5 (or to 12V max). And it has two pots for adjusting min/max.

Quote
Just scale it using a y = mX +C type of formula. Think about it.

I wish that scaling would be a default when passing a value to a limited range port. Like in Isadora.

Can you please explain your formula, if it's simple.
i am trying to get the range 200-13000 squeezed into 0-255.

(looking at this right now  :-? http://www.mathsisfun.com/equation_of_line.html)

Thank you humbly

fubbi

146  Forum 2005-2010 (read only) / Interfacing / ping to AC - scaling values on: December 03, 2008, 05:52:41 pm
hello

I am combinging a parallax Ping ultrasonic sensor with a DC controlled dimmer
http://www.parallax.com/Store/Sensors/ObjectDetection/tabid/176/ProductID/92/List/1/Default.aspx?SortField=ProductName,ProductName.
http://www.vellemanprojects.com/ot/en/product/view/?id=354314.

my question is, i will control the dimmer with an analogue PWM value right? so how do i scale the values the PING sensor gives me down to a 0-255 range, or a 0-5v range. must i use a function, or can this be automated?

thank you

fubbi
147  Forum 2005-2010 (read only) / Exhibition / Re: Breathalyzer with MQ-3 and Arduino on: August 23, 2010, 01:10:32 pm
http://en.wikipedia.org/wiki/Blood_alcohol_content

various cryptic charts, should tell you how many beers to drink to get enlighted  smiley-wink

fubbi
148  Forum 2005-2010 (read only) / Exhibition / Re: Breathalyzer with MQ-3 and Arduino on: June 29, 2010, 09:22:36 am
hi

I am thinking of building something similar. Did you feel that the range of the MQ3 was enough? I am looking at the TGS 2620 which is far more sensitive and three times more expensive. Or is that overkill for alcohol testing?

thanks

fubbi
149  Forum 2005-2010 (read only) / Exhibition / Re: That's Alcohol! on: July 16, 2010, 05:43:18 am
I got it hooked up and it reading fine. How hot did yours get? Mine is pretty hot, a little scary...

using a 1k resistor

fubbi
150  Forum 2005-2010 (read only) / Exhibition / Re: That's Alcohol! on: July 16, 2010, 05:02:13 am
Hi

yes the script was really simple. However, the pins on the 822 are confusing. I found tutorials for the similar MQ-3 but I have difficulties translating those to the 822.

Do you remember the pin order by any chance?

thanks
Pages: 1 ... 8 9 [10] 11