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1  Using Arduino / LEDs and Multiplexing / Re: flip dot display with shift register question on: August 26, 2013, 11:51:54 am
yeah
2  Using Arduino / LEDs and Multiplexing / Re: flip dot display with shift register question on: August 26, 2013, 11:28:28 am
Im not sure what you mean.  I dont know yet how the H bridge would be connected to the system. 

 if i have shit registers connected to each row or coulomb, couldn't i just change the polarity there.  Like for one coulomb I would make it 1, then for the row 0 to flip one way, then just switch to go the other?  that would make it so no H birdge would be needed
3  Using Arduino / LEDs and Multiplexing / Re: LED HULAHOOP... err... on: August 26, 2013, 10:54:07 am
i'm not sure exactly what your confused about in the code, but in the main loop you just want to do an analog write the 3 pin (red, Green, Blue) that are on your arduino, and keep changing the values to make cool effects.  So for a green fade, write the pin that controls the green to 255, then the others to zero, the every time the loop runs decrease the green

in void loop

i == 255;
analogWrite(greenpin, i);
i = i - 5;

4  Using Arduino / LEDs and Multiplexing / flip dot display with shift register question on: August 26, 2013, 10:34:36 am
Hey guys, so soon ill get my hands on a flip dot display from an old bus, and i'm starting to think about the circuit.  I'll multiplex the dots, and use and H bridge to change polarity with a bunch of 8 bit shift registers for the coulombs and rows.  I started to think about power and got very confused.  With the shift registers, the latch pin will only be enabled when all the bits are in place, the everything will turn on exactly at once.  Thats a lot of current.  For each dot i might need around 400 ma, and 4.5 volts, so i need to do them a couple at a time.  I was going to put a transistor IC after the shift registers also.  How should i go about this problem? 

Thanks
5  Using Arduino / Project Guidance / Re: values on my temp project slowly increase on: August 08, 2013, 07:18:51 pm
you said to check the output voltage from the sensor, and the Vin for the system, not the Aref
6  Using Arduino / Project Guidance / Re: values on my temp project slowly increase on: August 08, 2013, 05:20:06 pm
both numbers are stable
7  Using Arduino / Project Guidance / Re: values on my temp project slowly increase on: August 08, 2013, 05:02:01 pm
its being plugged into a wall outlet

Quote
When you want a lower and / or more stable reference than the supply.

Could the problem be that it is too unstable? , and is it self heating?
8  Using Arduino / Project Guidance / Re: values on my temp project slowly increase on: August 08, 2013, 02:37:24 pm
i using another microcontroller called an m2, pritty much an arduino, but im powering it with a cell charger with usb connection, its maintains about 4.9 volts, my code accounts for that exact voltage, but should i feed that into aref?  When do you use Aref?
9  Using Arduino / Project Guidance / Re: values on my temp project slowly increase on: August 07, 2013, 11:07:28 pm
i dont have any resistors on the lm34, and 330 ohm ones on each pin for the 7 segment
10  Using Arduino / Project Guidance / values on my temp project slowly increase on: August 07, 2013, 10:06:52 pm
http://www.flickr.com/photos/99469359@N03/9460897137

So i used a lm34 and two BCD ICs with 2 7 segments to read out temperature in F.  I thought it was all good, but ive run into two issues.  First the temp all ways starts pritty low, around 50, and has to work its way up to the ballpark temp for around 10 min.  Second when i leave it on for a while the temp just keeps slowly rising.  From the picture i'm wondering if the lm34 sensor is too close to the 7 segments, and so when they start getting warm it slowly moves the temp up, also the temp does plateau, and that temp does change depending on the actual temp.  Its reading a value about 10 degrees higher. also why does it start low when i turn the system on? Does the lm34 need time to get going? Ill post code below.

At first i thought the sensor was just busted, but when i blow on it or touch my fingers to it, it responds perfectly.

    
Code:
int a1 = D5;
        int b1 = D6;
        int c1 = D4;
        int d1 = D3;
    
        int a2 = D0;
        int b2 = B2;
        int c2 = B3;
        int d2 = B1;
    
        m_red(OFF);

    for(;;){
        
        
        
        int rawtemp_val = m_adc(6);
        long tempF = (rawtemp_val * 490L / 1024L);
        
        int digit_1 = tempF / 10;
        int digit_2 = tempF % 10;
        
  
      
        
        
        switch(digit_1)
        {
            case 0:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , OFF );
                m_gpio_out( b1 , OFF );
                m_gpio_out( a1 , OFF );
                break;
            case 1:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , OFF );
                m_gpio_out( b1 , OFF );
                m_gpio_out( a1 , ON );
                break;
            case 2:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , OFF );
                m_gpio_out( b1 , ON );
                m_gpio_out( a1 , OFF );
                break;
            case 3:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , OFF );
                m_gpio_out( b1 , ON );
                m_gpio_out( a1 , ON );
                break;
            case 4:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , ON );
                m_gpio_out( b1 , OFF );
                m_gpio_out( a1 , OFF );
                break;
            case 5:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , ON );
                m_gpio_out( b1 , OFF );
                m_gpio_out( a1 , ON );
                break;
            case 6:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , ON );
                m_gpio_out( b1 , ON );
                m_gpio_out( a1 , OFF );
                break;
            case 7:
                m_gpio_out( d1 , OFF );
                m_gpio_out( c1 , ON );
                m_gpio_out( b1 , ON );
                m_gpio_out( a1 , ON );
                break;
            case 8:
                m_gpio_out( d1 , ON );
                m_gpio_out( c1 , OFF );
                m_gpio_out( b1 , OFF );
                m_gpio_out( a1 , OFF );
                break;
            case 9:
                m_gpio_out( d1 , ON );
                m_gpio_out( c1 , OFF );
                m_gpio_out( b1 , OFF );
                m_gpio_out( a1 , ON );
                break;
            default:
                m_gpio_out( d1 , ON );
                m_gpio_out( c1 , ON );
                m_gpio_out( b1 , ON );
                m_gpio_out( a1 , ON );
                break;
        }
        switch(digit_2)
        {
            case 0:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , OFF );
                m_gpio_out( b2 , OFF );
                m_gpio_out( a2 , OFF );
                break;
            case 1:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , OFF );
                m_gpio_out( b2 , OFF );
                m_gpio_out( a2 , ON );
                break;
            case 2:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , OFF );
                m_gpio_out( b2 , ON );
                m_gpio_out( a2 , OFF );
                break;
            case 3:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , OFF );
                m_gpio_out( b2 , ON );
                m_gpio_out( a2 , ON );
                break;
            case 4:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , ON );
                m_gpio_out( b2 , OFF );
                m_gpio_out( a2 , OFF );
                break;
            case 5:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , ON );
                m_gpio_out( b2 , OFF );
                m_gpio_out( a2 , ON );
                break;
            case 6:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , ON );
                m_gpio_out( b2 , ON );
                m_gpio_out( a2 , OFF );
                break;
            case 7:
                m_gpio_out( d2 , OFF );
                m_gpio_out( c2 , ON );
                m_gpio_out( b2 , ON );
                m_gpio_out( a2 , ON );
                break;
            case 8:
                m_gpio_out( d2 , ON );
                m_gpio_out( c2 , OFF );
                m_gpio_out( b2 , OFF );
                m_gpio_out( a2 , OFF );
                break;
            case 9:
                m_gpio_out( d2 , ON );
                m_gpio_out( c2 , OFF );
                m_gpio_out( b2 , OFF );
                m_gpio_out( a2 , ON );
                break;
            default:
                m_gpio_out( d2 , ON );
                m_gpio_out( c2 , ON );
                m_gpio_out( b2 , ON );
                m_gpio_out( a2 , ON );
                break;
11  Using Arduino / General Electronics / Re: Arduino, output voltage dropping on: August 03, 2013, 01:20:11 pm
okay, i might have got it.  I was keep the pin from the power rail in 5v of the arduino instead of putting it into Vin when i switched to the power source
12  Using Arduino / General Electronics / Re: Arduino, output voltage dropping on: August 03, 2013, 01:15:10 pm
that was my first instinct, but after i checked them all, i started to notice the pattern of how it only worked on my computer, the second i unplug the external 5v it starts going strong again
13  Using Arduino / General Electronics / Re: Arduino, output voltage dropping on: August 03, 2013, 01:08:40 pm
when its up to my computer the reading is 4.8 volts, which gives consistent serial readout, and the systems works good.  When its up to 5.03v from the power source heres a list of the serial temp reading, it never stop fluctuating

55
66
68
66
64
60
55
53
53
66
60
60
53
55
55
55
53
51
55
66
53
59
57
48
66
53
48
59
14  Using Arduino / General Electronics / Re: Arduino, output voltage dropping on: August 03, 2013, 01:01:11 pm
unfortunatly, it isnt working anymore, anywhere i give it power that isnt my computers usb, it gives odd values... i cant figure it out
15  Using Arduino / General Electronics / Re: Arduino, output voltage dropping on: August 03, 2013, 10:45:52 am
got it working, thanks everyone
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