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1  Using Arduino / Sensors / Re: RFID not reading? on: November 16, 2012, 02:01:53 pm
Okay, then I assume I should wire it directly from the 5v pin on the Arduino board.  Thankfully, I didn't brick it because the red light on the RFID board still comes on when I do a digitalWrite.
In any case, the problem is still there.
I think I realized what I'm doing wrong, though.  http://forums.parallax.com/showthread.php?129430-Interface-Arduino-to-RFID-Read-Write.  On this forum I see that there are codes (e.g. 0x01) for reading and writing.  Duh.  smiley-red  I'll have to do more research.
2  Using Arduino / Sensors / RFID not reading? on: November 16, 2012, 11:03:57 am
RFID shield: https://www.sparkfun.com/products/10406
RFID tag (blank): https://www.sparkfun.com/products/10128?
Arduino Board: ATMega Lite/ATMega 328

I have all the ground pins wired the the Arduino ground pin and I have "5v" wired to pin 6 (named "D6") for turning on manually.  SoftwareSerial had a note about pins: "Not all pins on the Mega and Mega 2560 support change interrupts, so only the following can be used for RX: 10, 11, 12, 13, 50, 51, 52, 53, 62, 63, 64, 65, 66, 67, 68, 69"

I used pin 13 for TX (named "B5") and pin 12 for RX (named "B4").  Here is my code:

Quote
#include <Streaming.h>
#include <SoftwareSerial.h>

// Pin numbers.
const int RX = 12;
const int TX = 13;
const int LED_ORANGE = 7;
const int LED_BLUE = 6;
const int TAG_IN = 14;
const int SHIELD = 6;

// Timing
const int SECOND = 1000;
const int BAUD_RATE = 19200 ;

SoftwareSerial mySerial(RX, TX);

void setup(){
  pinMode(SHIELD, OUTPUT);
  
  Serial.begin(BAUD_RATE);
  mySerial.begin(BAUD_RATE);
  
  Serial << "Powering RFID Reader..." << endl;
  digitalWrite(SHIELD, HIGH);
  
  Serial << "Initialized...";
}

void loop(){
  getRFIDInput();
  writeToRFID("HELLO!");
  delay(10);
}

void getRFIDInput(){
  int c = mySerial.read();
  if (c != -1){
    Serial << "Read character " << (char) c << endl;
  }
}

/**
 * write a message to an RFID tag.
 * @param message the message to write.
 */
void writeToRFID(char message[]){
  mySerial.write(message);
}


The problem is that the variable "c" (in method "getRFIDInput") is always -1 so I'm not reading a character.  Did I write to it correctly?  I've been following different tutorials online.  The only variations seem to be they're changing the format in which the data is; the basis, though seems to be SoftwareSerial.read() and SoftwareSerial.write().

So confuzzled.  smiley-confuse
3  Using Arduino / Microcontrollers / Re: ATMega Lite? What board is this? on: November 15, 2012, 05:07:58 pm
retrolefty, you are a savior!

Yeah, the pin mapping for the ATMega Lite is a little wonky.  Like pin 13 isn't D7...I found it's B5.  smiley-cry

Why it isn't the standard D7, I can't tell you.
4  Using Arduino / Microcontrollers / ATMega Lite? What board is this? on: November 15, 2012, 03:48:38 pm
So, this is how I got started on Arduino (probably not the best way).  I walked into a local electronics store and said "how do I get started on Arduino?"  they handed me a board...rather parts to an ATMega Lite board.  I soldered it together (first time soldering!  It actually works, believe it or not).
Then came the pin mapping.  So far, I have not seen any documentation whatsoever on the ATMega Lite board, which makes wiring a project a nightmare (especially since I need to hook up an RX and TX wire for an external board).  Does anyone know a pin mapping for this board?  The only site I see that has anything on the ATMega Lite board is this page: http://www.surplusgizmos.com/AtMega-Lite-Development-Board-Made-By-GizmosUSAcom_p_2057.html -- the only place that sells the darn thing.
In the meantime I'll try finding the pins myself...input pins are going to be hard, though.  smiley-confuse
5  Using Arduino / Sensors / Re: RFID Hardware Question on: November 07, 2012, 01:09:34 pm
Great, thank you.  I was starting to wonder if I was going crazy.  smiley-cry  I may be a newbie at Arduino, but I ain't stupid!  smiley-lol
6  Using Arduino / Sensors / RFID Hardware Question on: November 06, 2012, 05:45:12 pm
I wanted to do RFID development, so I bought myself an RFID Evaluation shield 13.6 mHz from sparkfun (https://www.sparkfun.com/products/10406).  I soldered male leads into A0 through A8, VIN through RST, RX through D7, and D8 through AREF.  I soldered female leads in holes for the MIFARE module (the center spot with parallel holes).  The only problem is that one set of holes (holes D8 through AREF) are misaligned by about a half hole's width away from holes RX to D7.   smiley-mad Therefore, the sets A0 through A8, VIN through RST, and RX to D7 fit into the breadboard, while holes D8 through AREF fall onto the border.  I've tried bending the male leads (I know, bad practice, but I was desperate) to force them into the holes but it still won't fit.  Any ideas to align the leads?
Was I descriptive enough?  I can provide a picture or illustration if needed.  Thanks.
[Edit]
I should probably also mention the leads are straight.  I checked them over and over again.  Even if they weren't straight, though, they'd have to be at a very odd angle to not go into the breadboard.  smiley-eek
7  Using Arduino / Programming Questions / Re: Trouble with "blink" program on: August 02, 2012, 11:16:51 am
Oh, sorry, figured it out.  I tried using an other LED.  As luck would have it, the LED was bad, I guess.  I have a blue LED blinking now!  smiley
Thanks.
8  Using Arduino / Programming Questions / Trouble with "blink" program on: August 02, 2012, 10:36:31 am
Hello, follks, I'm new here.  Please pardon this newbie question.  smiley-mr-green

Board: ATMegaLite (self-soldered)
Arduino board (from the board menu): Arduino Nano w/ ATMega328
Connection: D7 --> 220 Ohm resistor --> LED --> GRND [picture included]
Code: Arduino's "blink" example.

This is my first time running an arduino application, and so far, it's not easy.  I have the setup as described above: a 220 Ohm resistor connected to pin D7 (corresponding to Arduino Uno's pin 13) with the circuit ending at ground.  I have all this mounted on a breadboard.  When I upload the program, nothing happens.  Since I figured I had the wrong pin, I decided to modify the program to the following:

Code:
void loop() {
  Serial.print("Turning on LED. ");
  Serial.println(++led);
  pinMode(led, OUTPUT);
  digitalWrite(led, HIGH);
  delay (1000);
}

...in hopes that I would eventually turn on the right pin.  However, I got to pin 44 (starting form pin 1) without the LED turning on.

I know that this isn't a firmware problem since I'm able to run this program and at least get console output.

Attached is a picture of my board setup.  In a bit I'll be using a multimeter to see what I can figure out though voltage.

Also, a disclaimer: I'm not a hardware buff, so I'm inadvertently learning hardware at the same time as Arduino.   smiley-confuse

Thanks to all in advance for helping a newbie!  smiley
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