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1  Forum 2005-2010 (read only) / Troubleshooting / Re: arduino software install: fedora 8 amd64 on: May 21, 2008, 09:36:56 pm
I ran into problems with attempting to compile the source.  In their download section they have the binaries, just download that and replace the, and the RXTXcomm.jar files with theres.  Works like a champ.
2  Forum 2005-2010 (read only) / Troubleshooting / Re: arduino software install: fedora 8 amd64 on: May 18, 2008, 05:25:48 am
I am having the same issue under ubuntu, amd64 as well, any ideas?
3  Forum 2005-2010 (read only) / Interfacing / Re: Arduino and 1-wire on: March 25, 2008, 06:59:50 am
Yes I ran into that too, as I reported elsewhere - the family code for the 18B20 is different from that for the 18S20.   (There's a note one the Arduino OneWire page that mentions this.) Just replace the family code in the test (0x28) with the one for the 18B20 (0x10).  For the record, the DS1822 thermometer has yet another family code (0x22).

Awesome, Thanks, I must have missed the family code changed, I thought I read all the paged, my bad.

edit: Its working now, I am getting hex data out, which is great.  I saw this piece of code in the original code snip, I just want to make sure its an accurate conversion of the hex
Serial.print("read scratchpad  ");
  msb = pad[1];
  lsb = pad[0];
  if (msb <= 0x80)lsb = lsb/2;
  msb = msb & 0x80;
  if (msb >=0x80) lsb = (~lsb)+1;
  if (msb >=0x80) lsb = lsb/2;
  if (msb >=0x80) lsb = ((-1)*lsb);
  Serial.print("T =  ");
  Serial.print(" ");
4  Forum 2005-2010 (read only) / Interfacing / Re: Arduino and 1-wire on: March 24, 2008, 10:22:01 pm
does any one know if this works with the  DS18B20...

I have it hooked up per everything I have found here, in parasite mode, and all get is this
R=28 92 F1 7D 1 0 0 34 Device is not a DS18S20 family device

any ideas?
5  Forum 2005-2010 (read only) / Interfacing / Re: Earthmate II on: April 08, 2008, 10:48:48 am
If you have a spare npn transistor and a few resistors lying around you can probably make one. Have a search for schematics for the Arduino/Freeduino serial boards to see some examples. Also, if I recall correctly, the sense of the signal is reversed between RS232 levels and TTL levels and that may explain the gibberish.  The simple one transistor converters will reverse the sense as well as ensure the voltage levels are correct.


that was exactly what the problem was.  I found this schematic and used the rs232 to ttl section, now its working

thanks for the help!!!
6  Forum 2005-2010 (read only) / Interfacing / Re: Earthmate II on: April 08, 2008, 09:27:27 am
I am not clear how you have this connected. It sounds like you are using RS232 level lines (plus/minus 5 volts or more) that work when connected to a PC, to connect to digital pins on an Arduino. You would need a serial to TTL adapter to get the correct signal levels into the Arduino, are you using one and if so are you sure its working correctly?

Also, I had a very early Earthmate years ago and I think it needed the output looped back to the input in order work correctly. Hyperterminal may be echoing the signal but the Arduino doesn't do that, you may want to check if you need to wire the GPS input and output together to echo the data.

So my assumption that the serial data that is coming out is readable by softwareSerial is where I went astray because I am not using a TTL adapter.  I will look into getting one, thanks
7  Forum 2005-2010 (read only) / Interfacing / Re: Earthmate II on: April 08, 2008, 08:45:42 am
ok... I connected to the serial read and I am still getting gibberish... I must have missed something

the device works connected to the serial port on the computer at 4800/8/n/1

any ideas?
8  Forum 2005-2010 (read only) / Interfacing / Re: Earthmate II on: April 04, 2008, 07:08:51 pm
ok that makes since, next question would be since my understanding of baud is limited, is there a good way to determine the timeing? secondly would I need to put in a delay after each byte read also? or would waiting for the serial to be available be enough?

Also, the SoftwareSerial read function, does that not work the same way that the regular serial read function works.  My understanding is that the read function waits for data to be sent before it proceeds....
9  Forum 2005-2010 (read only) / Interfacing / Earthmate II on: April 04, 2008, 02:23:44 pm
ok, I am pulling my hair out here and I need some help.  I have an earthmate II gps unit that I am trying to get to communicate with the arduino.  I found the pinout information online to add the serial connection to the existing connector.  I have done this and it works perfectly when plugged into the serial port on the computer.  It spits out NMEA data with no issues.  Now I assume that a simple with SoftwareSerial should be able to recieve this data and spit it back out through the usb cable going to the computer...  or am I completely nuts?

here is a link with a picture of the current circuit. please ignore the thing that looks like a transistor its a one-wire thermestor which will be added back into the code once I get this working  smiley-wink

here is the code:
#include <SoftwareSerial.h>

#define rxPin 7 //device tx
#define txPin 8 //device rx
#define DTR 4

SoftwareSerial mySerial = SoftwareSerial(rxPin,txPin);

char gpsData[301];
int i;

void setup(){
  pinMode(rxPin, INPUT);
  pinMode(txPin, OUTPUT);
  pinMode(DTR, OUTPUT);

void loop(){
 for(i=0; i<=300; i++){
  gpsData[i] =;


here is a screen shot of the gibberish I get

and here is the pinout information for the device.  It explains the DTR pin, but basically it needs to be high for the gps to be on

Any help you can offer would be greatly appreciated.
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