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16  Using Arduino / General Electronics / Re: UK Power supply issue, recommendation needed. on: October 18, 2012, 09:48:30 am
https://www.sparkfun.com/products/9363

Here is the LCD
17  Using Arduino / General Electronics / UK Power supply issue, recommendation needed. on: October 18, 2012, 09:40:46 am
Hi,
I'm running an UNO with an Arduino Ethernet shield and a sparkfun color LCD shield.

When I use a 12V, 2A, center positive  power source it resets itself every once in a while and gets very hot.

When I use a 9V, 300mA, 2.7VA , center positive power source it doesn't power the screen properly.

I am wondering if using a USB power adapter will make any difference.

What power supply would you recommend?

Thank you.
18  Using Arduino / General Electronics / Re: Connector suggestion - Simple question on: October 17, 2012, 09:35:02 am
okay thanks. I can't take the header pins off.. it's on an LCD shield suspended by the header pins above an Ethernet shield.. It'd go all wonky if I did that.

I've got a crimping tool, that's no problem. The place where I normally get my parts in the UK doesn't seem to stock the right type of crimp pin though. Maplin seems useless as well. Any ideas where I can pick some up?
19  Using Arduino / General Electronics / Connector suggestion - Simple question on: October 17, 2012, 09:13:23 am
At the moment I have three cables sticking out of the header pins on the top of my arduino. These control a relay. Two side by side, one on it's own.
They are not very secure, movement can sometimes pull them loose.

What type of connector do I need to attach these to the arduino to stop them coming loose?

I'm guessing a male header pin but I can't find anything that looks right anywhere.
20  Community / Bar Sport / Recycling/Hacking joke video on: October 16, 2012, 09:21:08 am
Just found this, it's old but I thought it was funny

21  Using Arduino / Programming Questions / Re: How do we copy a section of a char array that doesn't start at the beginning? on: October 14, 2012, 11:39:33 am
If I want to split a 140 char array into chars of 21 length  for display on an LCD screen, what command/s do I need to do so?

This program logically does:

Code:
static const int lcd_width = 20;

void print_large_array (const char *array, size_t len)
{
    size_t i;
    char small_array[21];

    if (len == 0)
        len = strlen (array);                // figure out length if not passed

    while (len > 0) {
        size_t len2 = (len > lcd_width) ? lcd_width : len;
        for (i = 0; i < len2; i++)
            small_array[i] = array[i];

        small_array[len2] = '\0';
        lcd.println (small_array);
        array += len2;                        // reset pointer/len for next iteration
        len -= len2;
    }
}

Thanks. I found this works, although due to having to draw a graphic.box to the screen before each line of code, I can't have it scrolling very fast. This seems to be interfering with my Ethernet connection as it's holding up my loop();
22  Using Arduino / Sensors / Re: Water level sensor advice on: October 12, 2012, 01:06:08 pm

I was looking at vertical floats.
I don't really want to have to cut through the bottom of the water tank because it's just one more hole onto the electronics, but it is a possibility. I need a very narrow float. I have about 25mm to play with at the bottom of the tank.
Also, if the water boils and makes the float switch, it might cut the circuit to the relay controlling the boil. But could be solved with a short timer of the connection time.

I'll think about it.
Thanks
23  Using Arduino / Programming Questions / Re: How do we copy a section of a char array that doesn't start at the beginning? on: October 12, 2012, 11:15:21 am
IF the goal is really line wrapping there are other ways to handle this.

--- bill

Care to elaborate? I have a 140 word tweet that regularly changes. I need to draw it across 6 21 character lines at the bottom of a sparkfun color LCD shield.

Any method you have of doing this will be an education to me.

If you are trying to text wrap with the gLCD library, that feature will be built into v3.1 which should be ready tonight or tomorrow.

That's great news Tom. I'll keep an eye out for it. The more methods I learn, the quicker I'll stop asking questions and be able to help more.
24  Using Arduino / Programming Questions / Re: How do we copy a section of a char array that doesn't start at the beginning? on: October 12, 2012, 10:43:54 am
I have looked through http://www.nongnu.org/avr-libc/user-manual/group__avr__string.html but I can't seem to find anything that will copy from a certain point within the array.
25  Using Arduino / Programming Questions / How do we copy a section of a char array that doesn't start at the beginning? on: October 12, 2012, 10:32:48 am
If I want to split a 140 char array into chars of 21 length  for display on an LCD screen, what command/s do I need to do so?



26  Using Arduino / Displays / Re: Nokia LCD display shield question on: October 11, 2012, 05:58:56 pm
I'd like a little guidance with how to write this if that is okay. I'm going to type it out how I think it should be structured (to get text scrolling).

We don't know how big the char string will be as it is variable in length depending on the tweet we are displaying.
We are printing at the following location

Code:
graphic.Box (1,70,128,79,0);
      graphic.setForeColour(GLCD_CYAN); //Text is coloured CYAN
      graphic.setCoordinate(1,70);
      graphic.print(dataStr); //This is stationary text

so I think it should go like this (roughly). .

graphic.setForeColour(GLCD_CYAN);       //set the text colour
graphic.setCoordinate(1,70);                //set the coordinates for the string to be drawn
tempString = dataStr[i+1];                       //create a temporary string to use as the display. Put an extra character on the end

while (tempString >1 char in length){
graphic.Box (1,70,128,79,0);                      //first clear the screen section from the last tweet
graphic.print(tempString);                   //print the tempString
tempString (Magically cut the first char out of the tempString) //perform magic
}

As you can see, help. Please. Thank you.
27  Using Arduino / Sensors / Water level sensor advice on: October 11, 2012, 06:37:48 am
Hi,
I need to measure the water level inside a coffee maker tank.
I bought an 8 inch eTape sensor
( )
and was advised to cut it down to the size I needed and seal the end with silicone. Unfortunately this didn't work. It would have worked but the tank was still to short to use the tape.

I need another way of measuring water level over a five inch, curved, plastic surface.

Basically I'm going to use the sensor to measure if the device has water in it. This will stop the unit from attempting  a brew if it is empty. This will save the glass jug heating up for nothing and possibly breaking. It also alerts me that I can't brew via twitter. I could do this by having a variable resistor spread over the five inches.
or I could possibly have several pairs of exposed wires glued down the side of the tank. This would need to send a current through the water to detect which ones are wet. Not ideal.

Do you know of any methods or sensors that fit my needs?

Thank you.

28  Using Arduino / Displays / Re: Sparkfun color LCD shield question, possible problem. on: October 10, 2012, 08:15:23 am
Have you tried switching the epson to phillips in the code?
29  Using Arduino / Displays / Re: Nokia LCD display shield question on: October 08, 2012, 09:19:59 am
Sure. I'll give you a copy of what I'm making when I'm done... probably this week.

Thanks very much.
30  Using Arduino / Displays / Re: Nokia LCD display shield question on: October 08, 2012, 09:10:07 am
That makes a lot of sense. I knew it ffs. I just keep forgetting. 

Another issue, If I need to display 140 characters on one line, how do I make it scroll across the screen?
Is it a case of wiping the screen, deleting the first char and repeating until the message has gone?
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