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1  Using Arduino / Microcontrollers / Re: Question about PIC16C505 on: December 02, 2012, 01:16:08 am
I can just link you pictures if that's okay I didn't make the keypad itself I was apart of something I just took it off and was trying to use it with a project but what you're saying is that they aren't compatible?

Pictures:
http://i.imgur.com/3ylnr.jpg
http://i.imgur.com/O10OY.jpg
http://i.imgur.com/7IQLE.jpg

Well regardless thank you for the quick reply!
2  Using Arduino / Microcontrollers / Question about PIC16C505 on: December 02, 2012, 12:58:43 am
I have a PIC16c505 attached to a keypad I'm not too sure how it works but how would one go about retrieving values from the keypad? I took a look at the info but i wasn't too sure how one would go about receiving the information via arduino.
The document I was looking at is right here.
http://ww1.microchip.com/downloads/en/devicedoc/40192c.pdf
Ill keep investigating but If anyone could enlighten me I would really appreciate it.
3  Using Arduino / LEDs and Multiplexing / Re: Shift Registry Question on: October 16, 2012, 01:09:03 am
Oh alright thank you for your help I think ill just stick with the other solution since this would require 3 transistors.

The diagram to the other solution I was thinking of was this one https://dl.dropbox.com/u/31949989/Idea1.PNG
4  Using Arduino / LEDs and Multiplexing / Re: Shift Registry Question on: October 16, 2012, 12:11:42 am
@Osgeld:Okay thank you very much! smiley-grin
I think you need more than a diode - you need to have the WS2801 drive a transistor to sink current thru the LEDs.
See the figure 8 discussion on pages 9 & 10 of the datasheet.
WS2801 is still powered from 5V, the LED string with current limit resistor is powered from 12V.

Ah okay does it need an independent transistor for each color?(RBG)
I've read through those several times I'm a bit too newbie to completely understand that.

Also is my diagram wired up correctly?
5  Using Arduino / LEDs and Multiplexing / Re: Shift Registry Question on: October 15, 2012, 11:27:47 pm
thanks for all the replies guys and sorry about a late reply but all the parts just got here and I've tested out my circuit and it turns out I need more voltage.

I'm currently running 4 5050 LED's in series and it requires about 12 volts problem is the WS2801 only does 6 volts without a diode.

I have come up with two solutions...Include a diode and I was considering if this diode was the right one to use (If you guys could suggest any I would appreciate it)

Or would running 2 pairs of leds in parallel work better for my situation? (Diagram here: https://dl.dropbox.com/u/31949989/Idea1.PNG)

Diagram in series (https://dl.dropbox.com/u/31949989/asdasfsa.PNG)
6  Using Arduino / LEDs and Multiplexing / Re: Shift Registry Question on: October 09, 2012, 11:55:04 pm
Thanks for the reply I was reading through the datasheet and as a newbie to electronics I have no clue what most of it ment  but thank you for clearing some of it up, ill definite print this up and give it a good read.

Also @ Crossroads wow those chips are awesome I really wish I had seen those earlier they are great for the price...Ill try to use them on my next run quick question tho are they compatible with the WS2801 or would I have to use different systems for the chips?
7  Using Arduino / LEDs and Multiplexing / Re: Shift Registry Question on: October 09, 2012, 08:28:48 pm
Wow thank you for that link I already bought 50 for 20 usd and it was free shipping but on my next buy (Which i probly will need more) I will buy some from these.
Another question

Do you guys know any places where I can find good schematics examples for the WS2801? I'm not too sure how I should go about wiring I don't want to mess anything up.
I've seen this example and it looks great but What resistors are they using and what other chips are on there? http://learn.adafruit.com/system/assets/assets/000/001/138/original/36mm-io.jpg?1342657099

Yeah I've seen some of maxims stuff its really nice but so expensive D:
8  Using Arduino / LEDs and Multiplexing / Shift Registry Question on: October 09, 2012, 06:22:19 pm
Hi guys I'm fairly new to eletronics and what not so I'm not too sure whats the best really...
I'm planning on making a pretty big LED wall but I'm not too sure what to use
I've seen a ton of video of people using the WS2801 but it's quite expensive the cheapest I've found is 50 for 20USD
I've also heard great things about the 74HC595 and it is quite cheaper 100 for 20 USD
so my question is Which one is better for a big LED wall?
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