Recently I made some comments about the VX1 Mini-Mobile phone.

Since then I’ve played about with the phone. And then I broke it.

The phone got knocked off the end of my workbench, after which it failed to work.

The phone now fails to recognise SIM cards, and rattles when shaken. This makes me think that the SIM contact mountings have broken.

This is shit. I’ve thrown a Nokia 3310 at a wall and it still read the SIM, even though half the keypad was snapped off.

Tesco have withdrawn the phone from sale, and are not offering replacements.  I was offered what is tantamount to a credit note against  other goods though.

The saying goes: “he who breaks something to understand it has left the path of wisdom”.

If it already broken, it is fair game.

So I’ll be taking one apart soon.

It has been a while since I’ve messed with the Dalek project, so this is just a brief update of the minor twiddling I’ve done.

Firstly, the Dalek now has a USB Type B socket on the rear of the casing replacing one of the “Dalek Bumps”, as shown:

USB B Socket, in place of Dalek Bump

Acquired from Maplin (part no N57FL), this USB Panel Mount Socket is reversible, with a Type A socket on one side, and a Type B on the other.

As a PC generally has a Type A socket, and the Arduino I’m using has a Type B socket, I opted to have the Type B on the outside.

This will allow the use of a normal A-B cable to connect between the PC and the case socket, and require a short A-B cable to connect between the case socket and the Arduino (as having a 3m cable curled round inside the thing seems a bit stupid).

Sadly, getting a short USB A-B cable isn’t easy. So I had to chop up an existing cable and butcher it.

All chopped and ready to solder

Bad soldering hidden by about 50cm of tape

Now, the Arduino can be left inside the Dalek case, which can be screwed shut again.

However, when the Arduino isn’t connected via the USB link, it loses power (tenuous link to the title of the post). Luckily, the Arduino Duemilanove that I’m using has a 2.1mm socket, and will run from a 9v battery.

So we need a PP3 9V battery clip, and a 2.1mm DC power plug.

Solder the battery clip’s black wire to the outside connection of the plug, and solder the battery clip’s red wire to the centre connection of the plug.

For clearer instructions, and clearer pictures (I have a crap camera), see the relevant page at Arduino Playground.

The yellow tape is not being used to hide a massive solder disaster this time, but merely to keep the wires together.

So, now I have a Dalek with a battery pack for the motors (from the original casing), a battery pack for the Arduino (ok, a PP3 taped inside), and a USB socket on the casing.

Now it can be programmed, unplugged, and be left to trundle into things.

So here is some code to make it wait for five seconds,  spin right for one second, wait for two seconds, spin left for one second, and repeat for ever (or until the power is removed):

// Project: Dalek control system
// Version 0.2 - Sit and spin
// Tony Blews tony@tonyblews.co.uk

int MotorDirectionR = 10;
int MotorDirectionL = 11;
int MotorPowerR     = 12;
int MotorPowerL     = 13;
long randNumber;

void setup()
{
 pinMode(MotorDirectionR, OUTPUT);
 pinMode(MotorDirectionL, OUTPUT);
 pinMode(MotorPowerR, OUTPUT);
 pinMode(MotorPowerL, OUTPUT);
   randomSeed(analogRead(0));

}

// modes for the motor control
// convention here is modeXX - where X is F for forward,
//S for stationary and B for backwards
// first X is the left motor, second X is the right one
// for direction control, the LOW if forward and HIGH is backward
// for power control, LOW is off and HIGH is on

// all stop
void modeSS()
{
 digitalWrite(MotorDirectionR, LOW);
 digitalWrite(MotorDirectionL, LOW);
 digitalWrite(MotorPowerR,LOW);
 digitalWrite(MotorPowerL,LOW);
}

// spin left
void modeBF()
{
 digitalWrite(MotorDirectionR, LOW);
 digitalWrite(MotorDirectionL, HIGH);
 digitalWrite(MotorPowerR,HIGH);
 digitalWrite(MotorPowerL,HIGH);
}

//spin right
void modeFB()
{
 digitalWrite(MotorDirectionR, HIGH);
 digitalWrite(MotorDirectionL, LOW);
 digitalWrite(MotorPowerR,HIGH);
 digitalWrite(MotorPowerL,HIGH);
}

//main program loop
void loop()
{
delay (5000);
modeFB ();
delay (1000);
modeSS ();
delay(2000);
modeBF();
delay(1000);
modeSS();
}

The next step will be to install some sensors.

Another day, another drunken tat-gadget purchase. This time it’s the VX1 Mini Mobile Phone, a phone designed to be cheap, cheerless, and as basic as something very basic. If it was a car, it would be a 1991 Škoda Favorit.

The phone, which offers less features than a Nokia 3110, is available from Tesco for the whopping price of £9.48. This is what it looks like, with the usual cigarette lighter for size comparison:

At 80x50x10.3mm, its small enough to bung in a pocket/bag/glovebox and forget about until you need it. The battery allegedly last for 90 hours, and you can chatter away for 100 minutes, or so they say.

You can make and recieve calls on it, and do the text message stuff, but that is about it. No games, no putting your own ringtones on it, no web browsing and certainly no fancy-pants apps that will annoy the hell out of your mates (if you have any left after installing that Vuvuzela thing).

This less-than-a-tenner phone isn’t locked to any network and does the GSM 900/1800 or 850/1900 thing, allowing you to pop your existing sim card into it. I’ve tried it on all the usual UK suspects and it works, with the exception of 3. 3 sims carry a warning not to insert them into 2g phone or they will become blocked, and I only have one 3 sim at the moment, which I don’t want to lose.

Talking of losing things, this is probably the main market for the phone. If you are the sort of numpty who can’t go out for a night on the lash without losing your phone in a taxi, this is the idea one for you. True, you’ll lose your number, and won’t be able to annoy your mates (those you have left) with the latest iDrone apps, but losing a ten quid phone is a lot less hassle that losing one worth £400*.

*Of course, the only reason why I don’t have four hundred and odd quids worth of phone is because I keep buying tat like this instead!