Hey, I just wanted to let you guys in the arduino forum know about the Tacoma Electronic Makers group that has been meeting in Tacoma for a few years. We are a small group and would love to expand, so why don't you join us? We meet on the second Sunday of each month at FabLab Tacoma.
Signup to our mailing list or get connected on facebook through our website:
www.tacomamakers.com
Our next meeting is on the 13th at 1:30.

I am trying to use my Arduino Duemilanove to program a Attiny 85 microcontroller. I am running Arduino on my Windows 7 Toshiba laptop. I have done this before with a DIP in Arduino version 0022 but cannot seem to get it to work now.
I followed this tutorial: http://hlt.media.mit.edu/?p=1706
I connected all the pins (PWR, GND, SCLK, MISO, etc...) to the appropriate arduino pins and to the attiny through a header on the board it is affixed to. I double checked all the connections but still cannot get the chip to program. I tried to program it from arduino 0022 and 1.0 but to no avail.

The ISP programming sketch uploads fine but when I try to upload the code to the attiny this is the error message I get Arduino 1.0:

Code:

Binary sketch size: 818 bytes (of a 8192 byte maximum)
avrdude: please define PAGEL and BS2 signals in the configuration file for part ATtiny85
avrdude: stk500_program_enable(): protocol error, expect=0x14, resp=0x50
avrdude: initialization failed, rc=-1
         Double check connections and try again, or use -F to override
         this check.

avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

If someone could point me to a solution I would be greatly appreciative.
-Peter

I have a sketch on my Arduino sending an analog pin value to the computer through serial.println.... It is working fine. I am trying to read that value through python using the PySerial library. My python code is this:
import serial
ser = serial.Serial('COM4', 9600)
while 1:
    ser.readline()
When I put the code in a line at a time through the python shell it works but if I try to run it from a saved file (F5) it gives me this error:
Traceback (most recent call last):
  File "C:\Users\Peter\Dropbox\3D printer\Python Interface.py", line 2, in <module>
    ser = serial.Serial('COM4', 9600)
  File "C:\Python27\lib\site-packages\serial\serialwin32.py", line 30, in __init__
    SerialBase.__init__(self, *args, **kwargs)
  File "C:\Python27\lib\site-packages\serial\serialutil.py", line 260, in __init__
    self.open()
  File "C:\Python27\lib\site-packages\serial\serialwin32.py", line 56, in open
    raise SerialException("could not open port %s: %s" % (self.portstr, ctypes.WinError()))
SerialException: could not open port COM4: [Error 2] The system cannot find the file specified.


I am running the code on a win7 64 bit Toshiba laptop running win7 ultimate 32 bit. Python verision 2.7.2
Thanks in advance,
Peter

Well cr0sh I agree with you on that. In the next version I would like to have dual trace and have better time info. Perhaps even some memory features.
@Onions: Using the library I have (also on my website peterdavenport.posterous.com) it is really simple to write code for the screen.

Code:

LCDSetLine(45, 5, 21, 130, BLACK);

Is basically the form all the screen commands are in with the numbers being ordered sets of the x and y positions of the object to be drawn. The library takes care of the LCD protocol stuff.

So I did this project a few months ago, actually probably almost eight. Anyway, time flew by and I finally got it posted up on the net.
Basically, this project uses SparkFun's Color LCD Shield to graph voltage on an analog pin in real time across the screen.
http://peterdavenport.posterous.com/2011/04/arduino-o-scope.html

Why does the DC motor have 4 pins, or age you running two? Are you using a motor driver?

I am trying to convert a string constructed by the textstring library into a float.

Code:

String xstr = String(10);
...
         float xwantedpos = float(xstr);
         Serial.println(xwantedpos);
...

I get this error message:
error: invalid cast from type 'String' to type 'float'

how can I convert these types of strings to floats/doubles.

I am on widows and i tried to use the COM_ But that wouldn't work either.  

I am trying to recognize incoming signals coming from my arduino in pythion. I have this code :
import serial
ser = serial.Serial('/dev/tty.usbserial', 9600)
while 1:
    ser.readline()

But I get this error message:

Traceback (most recent call last):
  File "C:/Documents and Settings/ad/Desktop/test", line 2, in <module>
    ser = serial.Serial('/dev/tty.usbserial', 9600)
  File "C:\Python25\lib\site-packages\serial\serialutil.py", line 171, in __init__
    self.open()
  File "C:\Python25\lib\site-packages\serial\serialwin32.py", line 53, in open
    raise SerialException("could not open port %s: %s" % (self.portstr, msg))
SerialException: could not open port /dev/tty.usbserial: (3, 'CreateFile', 'The system cannot find the path specified.')



So any ideas of how to make it work?

Maker sure your java is updated and installed. I had that problem once and had to open it with the bat file.

I am making a G-code interpreter and have run into an issue in the positioning system.

This code works, but the stepper I am using isn't acreate down to 0.01 mm:
 

Code:

void xSmall(){
  if(abs( xCurrent - xDouble ) <= 0.005){
  //do nothing!!!
  }else{
    if(xCurrent < xDouble){  //Do we move up?
//Move tward xDouble by 0.01 units
  digitalWrite(x1, HIGH);
  delay(d);
  digitalWrite(x1, LOW);
  
  digitalWrite(x2, HIGH);
  delay(d);
  digitalWrite(x2, LOW);

  digitalWrite(x3, HIGH);
  delay(d);
  digitalWrite(x3, LOW);
  
  digitalWrite(x4, HIGH);
  delay(d);
  digitalWrite(x4, LOW);

      xCurrent = xCurrent + 0.01; //write in current location
    }else{
 //Move tward xDouble by 0.01 units
  digitalWrite(x4, HIGH);
  delay(d);
  digitalWrite(x4, LOW);
  
  digitalWrite(x3, HIGH);
  delay(d);
  digitalWrite(x3, LOW);

  digitalWrite(x2, HIGH);
  delay(d);
  digitalWrite(x2, LOW);
  
  digitalWrite(x1, HIGH);
  delay(d);
  digitalWrite(x1, LOW);

     xCurrent = xCurrent - 0.01; //write in current location
    }
  }
}
 

This code compensates for the inacreasy but is Doesn't work:

 

Code:

void xSmall(){
  if(abs( xCurrent - xDouble ) <= 0.25){
  //do nothing!!!
  }else{
    if(xCurrent < xDouble){  //Do we move up?
 // Move tward zDouble by 0.25 mm
  digitalWrite(x1, HIGH);
  delay(d);
  digitalWrite(x1, LOW);
  
  digitalWrite(x2, HIGH);
  delay(d);
  digitalWrite(x2, LOW);

  digitalWrite(x3, HIGH);
  delay(d);
  digitalWrite(x3, LOW);
  
  digitalWrite(x4, HIGH);
  delay(d);
  digitalWrite(x4, LOW);

      xCurrent = xCurrent + 0.25; //write in current location
    }else{
 // Move tward zDouble by 0.25 mm
  digitalWrite(x4, HIGH);
  delay(d);
  digitalWrite(x4, LOW);
  
  digitalWrite(x3, HIGH);
  delay(d);
  digitalWrite(x3, LOW);

  digitalWrite(x2, HIGH);
  delay(d);
  digitalWrite(x2, LOW);
  
  digitalWrite(x1, HIGH);
  delay(d);
  digitalWrite(x1, LOW);

     xCurrent = xCurrent - 0.25; //write in current location
    }
  }
}

I don't see any logical reason why it wouldn't work?  :-?

YEAY, i messed with it for about 10 min and now it is working!!!!

Thanks to everyone who posted!!!

abs is available but is still doesn't work.

Yea that looks like the issue. I tried the epsilon method but now the two variables being compared are thought to be equal when they are not. :-?

I am writing a G-code interpreter and have run into a problem. When the X and Y axis get to their desired position (Right now I just have it return the axis and a .01 unit movement over serial) they just move +0.01 and -0.01 back and forth.

How can I get it to stop it when it reaches the desired position?

Code:

#include <WString.h>                // include the String library
String inString = String(50);       // allocate a new String for the incoming group of chars.
String units = String(2);       // allocate a new String for the units setting. Inches or Milimeters.
String xstr = String(10);       // string for the X caricters to be dumped before thy become and double or float.
String ystr = String(10);       // string for the Y caricters to be dumped before thy become and double or float.
String zstr = String(10);       // string for the Z caricters to be dumped before thy become and double or float.
double xCurrent = 0;
double yCurrent = 0;
double zCurrent = 0;

double xDouble;
double yDouble;
double zDouble;

double xDiference;
double yDiference;
double Diference;

void setup() {
  Serial.begin(9600);               // open the serial port
  Serial.println("start");            // Say hello
}
void loop () {
  if(Serial.available() > 0) {      //add chars if they are avalible
  
    char inChar = Serial.read();    // read the incoming data as a char
    
      if (inChar == 'l'){           // If it is the end of the string decode the string and do the actions.
        char firstChar = inString.charAt(0);
        //start parsing string
        if (firstChar == 'G'){ //Is it a G-code
        GCodeParse();
        }
        else if (firstChar == 'M'){//Is it an M-code
        MCodeParse();
        }
        else{//If it is nether a G or M code send to the computer to continue.
         Serial.println("continue");
        }
        //stop parsing and erase string
        inString = 0;
      }
    else{
        inString.append(inChar); // if you're not at the end of the string, append the incoming character
    }

  }
}

void MCodeParse(){
if (inString.equals("M101")){
         Serial.println("Extruder on");
         //add code for turning on extruder  ---------------------------------------------------<<<
         Serial.println("continue"); // Tell the computer to go on.
}
else if (inString.equals("M103")){
         Serial.println("Extruder off");
         //add code for extruder off  ---------------------------------------------------<<<
         Serial.println("continue"); // Tell the computer to go on.
}
else if (inString.equals("M106")){
         Serial.println("Fan on");
         //add code for fan on  ---------------------------------------------------<<<
         Serial.println("continue"); // Tell the computer to go on.
}
else if (inString.equals("M107")){
         Serial.println("Fan off");
         //add code for fan of  ---------------------------------------------------<<<
         Serial.println("continue"); // Tell the computer to go on.
}
// ----------- do we need extruder P,I,and D gain? Do we need set temp or extrude speed -------------
else{
         Serial.println("continue"); // If unknow code tell the computer to go on.
}
}


void GCodeParse(){
  
if (inString.startsWith("G0 ") || inString.startsWith("G1 ")){ // Is the code for positioing?
         //Code for finding X Y and Z cordenents
         int xcharloc = inString.indexOf('X'); //find where the X code starts
         int ycharloc = inString.indexOf('Y'); //find where the Y code starts
         int zcharloc = inString.indexOf('Z'); //find where the Z code starts
        
         xcharloc = xcharloc + 1;// Code for finding what X is in the code
         ycharloc = ycharloc - 1;
         xstr = inString.substring(xcharloc, ycharloc);
         ycharloc = ycharloc + 1;
        
         ycharloc = ycharloc + 1; // Code for finding what Y is in the code
         zcharloc = zcharloc - 1;
         ystr = inString.substring(ycharloc, zcharloc);
         zcharloc = zcharloc + 1;

         int zlast = inString.length(); // Code for finding what z is in the code, This is some more complex code
         if(inString.contains("F")){
         int fcharloc = inString.indexOf('F'); //find where the F code starts
         zcharloc = zcharloc + 1;
         fcharloc = fcharloc - 1;
         zstr = inString.substring(zcharloc, fcharloc);
         zcharloc = zcharloc - 1;
         fcharloc = fcharloc + 1;  
         }else{
         zcharloc = zcharloc + 1;
         zstr = inString.substring(zcharloc, zlast);
         Serial.print(zstr);
         Serial.println(" <Z value");
         zcharloc = zcharloc - 1;
         }
        
         xDouble = atof(xstr); //convert string with x cordanents to double format
         yDouble = atof(ystr); //convert string with y cordanents to double format
         zDouble = atof(zstr); //convert string with z cordanents to double format
        
         Serial.print("X as a double : ");
         Serial.println(xDouble);
         Serial.print("Y as a double : ");
         Serial.println(yDouble);
         Serial.print("Z as a double : ");
         Serial.println(zDouble);
    
        if(zCurrent == zDouble){ // If a new Z position is not requested do nothing.
        }else{//if it is requested move the axie
        
           while(zCurrent < zDouble){  //Do we move up?
             //Move tward zDouble by 0.01 units
             Serial.print("z+");
             zCurrent = zCurrent + 0.01; //write in current location
           }
           while(zCurrent > zDouble){ //Or do we move down?
             //Move tward zDouble by 0.01 units
             Serial.print("z-");
             zCurrent = zCurrent - 0.01; //write in current location
           }
          
        }
        
        move();
        
        Serial.println("continue"); // Tell the computer to go on when you are done.
}

else if (inString.startsWith("G20 ")){
         units = "in";
         Serial.println("continue"); // Tell the computer to go on.
}
else if (inString.startsWith("G21 ")){
         units = "mm";
         Serial.println("continue"); // Tell the computer to go on.
}
// ---------------------------???Do we need "G28, G30, G90, G91, G92"??? Arcs? Dwells?--------------------------
else{
         Serial.println("continue"); // If unknow code tell the computer to go on.
}

}


void xBig(){
}
void yBig(){
}
void xSmall(){
  if(xDouble == xCurrent){
  //do nothing!!!
  }else{
    if(xCurrent < xDouble){  //Do we move up?
      Serial.print("x+"); //Move tward zDouble by 0.01 units
      xCurrent = xCurrent + 0.01; //write in current location
    }else{
      Serial.print("x-"); //Move tward zDouble by 0.01 units
     xCurrent = xCurrent - 0.01; //write in current location
    }
  }
}
void ySmall(){
  if(yDouble == yCurrent){
  //do nothing!!!
  }else{
   if(yCurrent < yDouble){  //Do we move up?
      Serial.print("y+"); //Move tward zDouble by 0.01 units
      yCurrent = yCurrent + 0.01; //write in current location
    }else{
      Serial.print("y-"); //Move tward zDouble by 0.01 units
     yCurrent = yCurrent - 0.01; //write in current location
    }
  }
}


void move(){
 while(xDouble != xCurrent||yDouble != yCurrent);{
  // Find the difference
if(yDiference > 0 && xDiference > 0){
if(xDouble > xCurrent){
  xDiference = xDouble - xCurrent;
}else{
 xDiference = xCurrent - xDouble;
}
if(yDouble > yCurrent){
  yDiference = yDouble - yCurrent;
}else{
 yDiference = yCurrent - yDouble;
}
if(xDiference > yDiference){
 Diference = xDiference/yDiference;
}else{
 Diference = yDiference/xDiference;
}                     // STOP finding the difference
}else{
}

 Serial.print(Diference); // Tell the godfather what the difference is.
 Serial.print("X: ");
 Serial.print(xCurrent);
 Serial.print("Y: ");
 Serial.println(yCurrent);

 if(xDiference > yDiference){
   xSmall();
   ySmall();
 }else{
   xSmall();
   ySmall();
 }
 
 
}


}

The Part I am having trouble with is the void xSmall(), ySmall(), and move().