Show Posts
Pages: [1] 2
1  Topics / Product Design / Re: Eagle ground plane and 5v on: November 24, 2011, 10:39:17 am
How do you decide when to use a polygon, for instance 5v, or to connect them all using Nets?

Thanks!
2  Topics / Product Design / Eagle ground plane and 5v on: November 23, 2011, 01:01:29 pm
I created a schematic for this post. I followed a tutorial and it explained how to create the board and ground plane. The tutorial indicated that all the grounds would be connected automatically. It also said the 5volts would be connected.

Using my attached schematic, when I create the board and subsequent ground plane will the grounds be connected? Will the 5vs be connected? Trying to verify I understood the tutorial correctly.

Thanks!

3  Topics / Product Design / Re: Eagle design / ATMEGA328 on: November 22, 2011, 04:24:44 pm
Ah now I get it!
Many Thanks!
4  Topics / Product Design / Re: Eagle design / ATMEGA328 on: November 22, 2011, 02:10:55 pm
How do I get to layout view? So far all I've used is schematics and board. Is layout view when you create the board and drag the components onto the board?

Thanks for your patience!
5  Topics / Product Design / Re: Eagle design / ATMEGA328 on: November 22, 2011, 12:43:33 pm
I have the dimensions, from digi, for the socket. In Eagle, all I'm seeing is an image with 28 numbered pins. Where do I find the dimensions in Eagle?

Thanks!
6  Topics / Product Design / Eagle design / ATMEGA328 on: November 22, 2011, 12:05:12 pm
I'm attempting to find an eagle library and file that has the correct spacing/pins for an ATMEGA328 socket.  SSOP28 from the Sparkfun library looks correct. My question is how do I know the pin spacing, both in the rows, and the distance between the rows will be correct?

Thanks!
7  Using Arduino / Microcontrollers / Re: Two chip sanity check on: September 13, 2011, 08:41:49 pm
Thanks guys!

You've given me much to think about. Back to the drawing board.
8  Using Arduino / Microcontrollers / Re: Two chip sanity check on: September 13, 2011, 05:01:16 pm
Oh, okay guys.... Thanks. The dim light is coming on.

Can I:
1. use an interrupt on one pin to increment a counter
2. set the counter to 0 and startTime to millis()
3. monitor millis() in the loop for millis()- startTime > 250
4. grab the accumulated value of the counter and do something with it.

The reason is so my code can keep looping and doing other stuff.

Am I getting closer.

Thanks!
9  Using Arduino / Microcontrollers / Re: Two chip sanity check on: September 13, 2011, 04:28:28 pm
I better check my understanding of loop.

void loop(){

long startTime = millis();
//lets call this counting
while(millis() - startTime < 250)
{
        count something
}

//lets call this blinking

if (ledState == LOW)
      ledState = HIGH;
    else
      ledState = LOW;


}

Am I correct in thinking that while counting is running for 250ms blinking is stopped or not running? So whatever the ledState is it will remain until counting is done?

Thanks!
10  Using Arduino / Microcontrollers / Re: Two chip sanity check on: September 13, 2011, 12:21:56 pm
I don't understand. Doesn't my 250ms loop, within void loop(){}, block the processor from doing anything with the pin listening for the IR sensor?

Thanks!
11  Using Arduino / Microcontrollers / Two chip sanity check on: September 13, 2011, 11:34:43 am
I've got two processes which are both time sensitive.

1. Every cycle I loop for .25 sec and wait for pulses coming in via an interrupt. I take the count of the pulses and update a LCD.

2. I continuously listen for signals coming in from an I.R. receiver and stop a timer if it's my I.R. beam coming in. I then update the same LCD

Does this require two chips? I'm using ATmega328s.

Thanks!

12  Using Arduino / General Electronics / Re: Can I use this current to power my Arduino on: July 26, 2011, 02:55:26 pm
There is no battery, it fires when spun with a starter rope as you suggested.

Thanks!
13  Using Arduino / General Electronics / Re: Can I use this current to power my Arduino on: July 26, 2011, 02:16:15 pm
Lefty,

I'd like use the current produced by the primary side of the coil for two things.

1. A trigger to count RPMs (working).
2. Can I use a capacitor to clean up the current and power the Arduino?

14  Using Arduino / General Electronics / Re: Can I use this current to power my Arduino on: July 26, 2011, 01:38:52 pm
Positive only.

15  Using Arduino / General Electronics / Can I use this current to power my Arduino on: July 26, 2011, 12:34:20 pm
I've got dirty power from the primary side of a small engine coil. I attached a 5v led with built in resistor to the primary side of the coil and ground. The led lights up and blinks with the pulse of the ignition.

On the scope I get a very quick 200 - 400 volt spike every time the coil fires. I'm new to using a scope and I'm very skeptical of my scope data. My next move was to use an opto isolator so Arduino can count the spikes. Works fine. The current goes from the primary coil wire to the + input side of the opto. The - input side of the opto is grounded back to the motor.

After the current runs through the opto isolator, can I run it into a capacitor and then a  voltage regulator to power Arduino? If so what size capacitor should I use and how should that circuit be constructed?

Thanks!

Pages: [1] 2