Arduino serial issues

[cmcclellan1993]

Hi everyone, I've been attempting to control my Roomba 2.1 with a arduino uno using a mini-din serial connection between my arduino and the roomba. However, I'm having trouble with consistency. I'm using a test sketch (which I will paste at the end) right now to start off with, which should simply put the roomba into spot mode in an infinite loop. Every now and then it works, and the roomba responds by sending itself into spot mode, but most of the time it doesn't. Instead, when I upload the sketch to the arduino, the roomba goes from being on to off and then about two seconds later back on. Right now, all I have connected is the tx to rx connection and the grounded wires of the roomba.

void setup(){
Serial.begin(57600);
delay(500);
Serial.write(128);
delay(100);
Serial.write(130);
delay(100);
}
void loop(){
Serial.write(134);

delay(1000);


}

[mfortuna]

A couple things. What do you mean by roomba 2.1? If you are referring to a 400 series then 57600 is the correct BAUD rate, else use 115200.

Also, I am not sure what happens when you send a spot command every second. Try sending it just once or try blinking the LEDs in a loop.

[New2roomba]

This sketch won't do ANYTHING on a Discovery (4210 0504 07) when connected to an Uno R3 thru an appropriate cable. The Discovery works as expected on its own and with the Roomba Remote.
I'm working with the LEDs for now. I'll work with the drive motors once I get the lights figgered out.
What is the purpose of toggling DD when setting up the Roomba?

Thanks, in advance, for any assistance
/*
* Turn lights on & off
* --------------
* The following code came from "Bump-&-Turn" so it should(?) work
* Arduino pin 3 is connected to Roomba RXD
* Arduino pin 4 is connected to Roomba TXD
* Arduino pin 5 is connected to Roomba DD
*
*/
#include <SoftwareSerial.h>
SoftwareSerial Roomba(3,4);
int ddPin = 5;
int ledPin = 13;

void setup() {
pinMode(ddPin, OUTPUT); // sets the pins as output
pinMode(ledPin, OUTPUT); // sets the pins as output

digitalWrite(ledPin, HIGH); // Start Setup
// wake up the robot
digitalWrite(ddPin, HIGH);
delay(100);
digitalWrite(ddPin, LOW);
delay(500);
digitalWrite(ddPin, HIGH);
delay(2000);

// set up ROI to receive commands
Roomba.write(128); // START Roomba in PASSIVE mode
delay(50);
// Set baud rate
Roomba.write(129); // Baud command
Roomba.write(10); // 10 = 57600
Roomba.write(130); // CONTROL Roomba in SAFE mode
delay(50);
digitalWrite(ledPin, LOW); // finished setup
delay(2000);
}
void loop()
{
// This code came directly from "Hacking Roomba" page 32
digitalWrite(ledPin, HIGH);
Roomba.write(139); // LEDS command
Roomba.write(40); // Status & Spot green
Roomba.write(128); // Power medium amber
Roomba.write(128); // 50% bright
delay(4000);

Roomba.write(139); // LEDS command
Roomba.write(15); //Dirt Detect, MAX, Clean, Spot ON
Roomba.write(128); // Green Power
Roomba.write(255); // 100% on
delay(4000);
Roomba.write(139); // LEDS command
Roomba.write(16); // Red Status
Roomba.print(0); // Power color
Roomba.write(100); // Dim
delay(4000);
Roomba.print(139); // LEDS command
Roomba.print(48); // Amber Status
Roomba.print(0); // Power Green
Roomba.print(128); // 50%
delay(4500);
Roomba.print(139); // All off
Roomba.print(0);
Roomba.print(0);
Roomba.print(0);
digitalWrite(ledPin, LOW); // we've finished 1 loop
delay(3000);
}

[mfortuna]

I think dd toggle is supposed to wake up the roomba.

[mfortuna]

It has been a while since I messed with this but check out:
viewtopic.php?f=4&t=15779&hilit=Ultrasonic+create