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1  Using Arduino / LEDs and Multiplexing / Re: 7x71 LED display - font manipulation on: January 02, 2013, 02:51:21 am
Ok, it is a limitation of the ShiftOut function. I'm stretching my programming skills, might as well take it another notch...

On the links, it looks to me like the part that allows for rotation is specific to the display the code is written for so not something I could reuse. Also, it seems all the fonts are 8 bits tall and I only have 7 to work with. Am I missing something here?
2  Using Arduino / LEDs and Multiplexing / 7x71 LED display - font manipulation on: January 01, 2013, 11:32:39 pm
I have a display that I'm able to address each LED on. There are 71 columns and 7 rows. I'm multiplexing the rows. The columns are setup on a cascade of shift registers.

I've picked up a few different 5x7 fonts to try, most are similar to this: http://www.hwsw.no/snippets/5x7_LCD_font.php. All of them are turned sideways for my purpose. If I write out the binary block, I can basically rotate it counter-clockwise 90-degrees and get a properly oriented digit. I'd like to know how I can do this manually or if there is something else out there that already has it for me.

Second, the following code seems to print a full byte when I only have 6 bits to push to it. This results in three columns between letters instead of just the one which is undesireable. How can I restrict the number of bits pushed onto the shift register?

Code:
// Print a letter onto the display
void print_letter() //(char c)
{
  int i;
  char e[] = {0x1C,0x22,0x22,0x3E,0x22,0x22,0x00}; //letter layer from top to bottom

  for (i=0; i<rowCount; i++)
  {
    shiftOut(ser, clk, MSBFIRST, e[i]);
    digitalWrite(rows[i], LOW);
    delay(2);
    digitalWrite(rows[i], HIGH);
  }

}

The complete code can be found at https://github.com/MakeLV/LED_Signage/tree/Elizabeth if that would be helpful.
3  Using Arduino / Sensors / Temp/Humidity Sensor - Best value for this case? on: June 04, 2011, 11:33:48 pm
I want to track temperature and humidity in several locations around my house. I've seen the SHT15 and the DHT22 over at sparkfun. The DHT22 is clearly less expensive and as I understand it a little less accurate, but since I may end up with 5-10 sensors it is significant.

I'd like to have these sensors strung out around the house with Cat5e run to each of the sensors None of the runs would be over 50'. I'd like to minimize the number of pins I use on the Arduino as I'd like to also use it for other duties around the house including a control panel which is likely to demand a lot of pins with LEDs and an LCD screen, along with ethernet network access.

Can the DHT22's unique 1-wire-ish interface be daisy chained (like the Dallas 1-wire stuff)?
Will the DHT22's accuracy remain constant or drift and will it be consistent across a variety of DHT22s?

Should I expect problems with the SHT15's 2-wire interface across 50' of twisted pair?
Any chance the SHT15's permit daisy chaining?

Is their any amplification inherent in the daisy chaining process? In other words, do I need to consider the longest run between sensors or the run from the furthest sensor to the Arduino?

Is there another temp/humidity sensor available that would work better without breaking the budget, perhaps a Dallas 1-wire sensor?
What does it take to weatherproof these for outdoor use?
Are there other questions I should be asking of these sensors?
4  Forum 2005-2010 (read only) / Troubleshooting / Re: softwareSerial error arduino-0016 in ubuntu on: July 25, 2009, 09:08:55 am
did this ever get resolved?
5  Forum 2005-2010 (read only) / Bugs & Suggestions / Link to Millis() ref page from Blink Without Delay on: April 28, 2009, 06:33:21 pm
It would be nice if a link existed from http://arduino.cc/en/Tutorial/BlinkWithoutDelay to http://www.arduino.cc/en/Reference/Millis. That is probably the first place that a person like me will run into a millis(). It took me a bit to figure out what it was about. A simple link would have been handy. :-)
6  Forum 2005-2010 (read only) / Bugs & Suggestions / "switch quantity not an integer"? on: May 02, 2009, 03:05:10 pm
In comparing the documentation at http://arduino.cc/en/Reference/SwitchCase, it doesn't say anything about the case statement requiring an integer. I tried using a float and it complained that it wasn't an integer. Can I not use a float? (If so, could a mention be made on the reference page for others to clarify that. :-)

Also, can an operator be used in a case? For example

switch (time) {
  case >300:
    do something;
  case >200:
    do something else;
  default:
}
7  Forum 2005-2010 (read only) / Syntax & Programs / Re: Arduino Emulator? on: January 18, 2010, 08:24:33 am
Yeah scrounging has become something I find myself doing. I've taken a few old printers apart and a scanner as well, but I don't know enough about the components I'm dealing with to know how to use them or identify them. How can I improve my skill in this area?
8  Forum 2005-2010 (read only) / Syntax & Programs / Arduino Emulator? on: January 17, 2010, 03:41:51 pm
It occurred to me that I'd play around with stuff a good bit more if I didn't have to shell out as much money. This made me wonder if there is an Arduino emulator or electronics emulator that includes an Arduino that I could plug in various components (or design them) and then watch the pieces interact with each other. Have you heard of such a thing?

In the end, I'd probably end up spending more money on all the cool things I've built and now want to see in reality. :-)
9  Forum 2005-2010 (read only) / Syntax & Programs / Re: Sending a string over Serial on: July 19, 2009, 06:30:23 pm
AWOL, I welcome your example. That would add value to the conversation. AlphaBeta's example was about 20 lines and I consider it valuable because it both answered my question and showed me how to get around my confusion.
10  Forum 2005-2010 (read only) / Syntax & Programs / Re: Sending a string over Serial on: July 19, 2009, 11:53:47 am
Thanks AlphaBeta.

So strictly speaking it doesn't receive strings. I can't just run Serial.read(var, STRING) or something like that, I need 20+ lines of code to receives many characters and put them together into a string.

I was hoping for something shorter, but I guess this falls under the saving space argument?
11  Forum 2005-2010 (read only) / Syntax & Programs / Re: Sending a string over Serial on: July 18, 2009, 09:59:45 am
Could you provide some code? All I've seen and been able to do has been dealing with individual characters at a time.
12  Forum 2005-2010 (read only) / Syntax & Programs / Sending a string over Serial on: July 17, 2009, 10:11:51 pm
Is it possible to send a string over Serial to the Arduino?

I have the Arduino hooked up to a Fon router's serial connection, but can't send commands without hardcoding them into the sketch. I'd like to be able to just send commands through the Arduino IDE or maybe some other term program on my mac.

I'm currently thinking my alternative is to build a menu which accepts a single character and send the corresponding string to the router. That's not real appealing though due to lack of flexibility.
13  Forum 2005-2010 (read only) / Syntax & Programs / Re: DTMF decoding using a decoder chip on: July 17, 2009, 09:57:09 am
Oh, PIN D :-) That space alone takes me in the proper direction. Thanks for explaining it further. That makes a lot of sense.

I was looking around the web and found another Mitel chip that does the CID stuff, MT88E46. I'll probably not get around to it, but I've got ideas running in my head that make that chip look really interesting.
14  Forum 2005-2010 (read only) / Syntax & Programs / Re: DTMF decoding using a decoder chip on: July 17, 2009, 12:25:45 am
Kg4wsv, thanks for posting that code. I'm learning a lot pouring over it. A couple questions... What does PIND in the code do? I don't see it declared anywhere.

Also, any thoughts on if it would be possible to limit config access to certain phones by using CallerID info? Can you get that out of the mt8870?
15  Forum 2005-2010 (read only) / Syntax & Programs / Re: Fold up / hide large pieces of code on: May 06, 2009, 12:57:29 pm
Also, the tabs seem to provide a bit of separation of code. They might be something to consider.
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