Show Posts
Pages: 1 ... 29 30 [31] 32 33 ... 102
451  Using Arduino / Project Guidance / Re: Sending DIY code through IR on: April 15, 2014, 10:31:17 pm
I would have to give each Arduino a number because the number is programmed via software. Is there an easy way to give it a hardware number? I’m thinking about a DIP-switch or something? But then I need a lot of inputs to read the switch.
Depends on how many different identities you want. One way is to use a voltage divider and measure the voltage on an analogue pin.  A 10K resistor between pin A0 and ground on each Arduino and a different value resistor (1K to 100K) between pin A0 and 5V on each one. The voltage on A0 can be translated into your identity by the ADC and some code. The identity can be easily changed simply by changing one resistor. Cheap, easy and only uses one pin.
452  Using Arduino / Project Guidance / Re: Advice on programming a accessory decoder for a computer controlle train layout. on: April 15, 2014, 12:04:02 am
I've expanded my scope some, utilizing the idea of Arduino in further ways. I was toying with the idea of RFID tags.
I've also been looking into RFID tags. There appear to be 3 different kinds. Low frequency, high frequency and UHF. Many of the tags I've seen don't specify which of these they use.  smiley-mad
I've been recommended some very small tags, about the size of a grain of rice, that are used as pet (cat and dog) chips. They come with an 'injector' (which we wouldn't need) and cost £3.00 (about 3.30 Euros) each. I'm trying to find out if they are low frequency types, whether they can be bought without the injector and if they are programmable or their code is fixed. I'll need over 30 of them for my automatic hump shunting yard.

Originally I was just going to use a simple reed switches. The idea was that I could have passenger trains that'd trip them and automatically pull into stations. I expanded this idea further though as I found too many limitations with such a simple system.
Depending on what scale you're working in, it's possible to use reed switches to identify a small number of different trains by using two magnets, at different distances apart, on each train. You wire the reed switches in series and if the distance between the reeds matches the distance between the magnets, both of them will be closed at the same time. You need only n+1 reeds to detect n different trains, as one reed is common to all the others.
453  Using Arduino / Project Guidance / Re: Help/Guidance!!!What to use? Encoders dont really help(wheels slippage)! on: April 14, 2014, 11:13:04 pm
If someone picks your car up and replaces it in the wrong place, no amount of 'remembering' will get it back to point B. Even a slight misplacement at point A or a slight bump in the road, over a long distance, could mean it doesn't get to point B by 'remembering' the route. Think about how difficult it is to score a 'strike' in 10 pin bowling where you can see the target (the pins). Now imagine being blindfolded and being spun around three times before you pick up the ball. You're never going to do it by 'remembering', but that is what you're asking of your car. Forget about remembering the route.

What you need is some sort of beacon at point B that your car can head towards, or a track/line for it to follow.
454  Using Arduino / Programming Questions / Re: Help with modulo. 25%10 always rounds off to 6. on: April 13, 2014, 05:15:00 pm
void processNumber(int number)
  int x;
  unsigned int ones;
  int tens;
I don't know if it's what's causing your problem but you don't need to round (number) before dividing it by 10 as tens is an int and can't hold the fractional part of the result.
Also, why the brackets around number?
You are calling a function from within a function. I seem to remember reading that that's a no-no.   smiley-confuse
455  Community / Bar Sport / Re: The next big thing in battery technology on: April 13, 2014, 01:37:37 pm
Their was a program on the tv the other day about battery's powered by sugar. They said they could be in mobile phones within 3 years or so.  You just put some more sugary water in them when they run out. The price of cheep fizzy drinks suggests they will be very cheep to run.
But as soon as they become popular, the price of sugar will double.
456  Using Arduino / Project Guidance / Re: Shooting Target Reset system on: April 12, 2014, 04:40:28 pm
I really want to have it wireless.  Right now I can reset the targets with the pull cord setup.  But dealing with 50+ yards of pull cord is not fun.   Same thing would happen if I had a wired switch.

I liked the blue tooth idea and setting up an app so that if I ever started selling these I would not have to provide a controller.  All I would have to do is tell them download my app and they would be set and be able to use their phone which nearly every human on the planet now has which would save money and keep the cost down.
   I   don't have a phone capable of downloading apps! But then, I'm not interested in target shooting.
457  Using Arduino / Project Guidance / Re: Newbie with a feasibility question. on: April 12, 2014, 04:26:29 pm
It appears that you need some kind of manometer.
Scroll to bottom of the page to see diagram.
458  Community / Bar Sport / Re: The perfect arduino murder! on: April 11, 2014, 10:39:13 pm
I would use it to snatch bad toupees.
A hair trigger?  smiley-mr-green
459  Community / Bar Sport / Re: The next big thing in battery technology on: April 11, 2014, 10:34:41 pm
The batteries may be smaller but a cable to carry 240A will have to be about 3/4" in diameter (each core) and probably cost $100 a meter/yard.
460  Development / Other Hardware Development / Re: List of tools for surface mount work on: April 11, 2014, 10:03:44 pm
Depending on your eyesight, a large magnifying glass on a stand might be useful.
461  Using Arduino / Displays / Re: TVout and RGB Video on: April 11, 2014, 09:39:00 pm
To add VGA colour to the TVout library and circuitry is quite simple.
The downside of this is that the TV can only output ONE colour at a time, but I think you will find this is better than just white all the time. The possibilities of this will give you 24bit colour !!!
I hope others can find this as useful and adaptable as I have - good luck :@)
Thanks for the schematic, but where will I find the code you're using?
462  Using Arduino / Project Guidance / Re: Shooting Target Reset system on: April 11, 2014, 02:42:41 pm
Why not just have a button and the Arduino by the shooter and connect it by wire to the servo at the target. An ABS project box would be all you need to protect the Arduino from pellets if it's next to the shooter. One Arduino can control several servos and switches, depending on which model you use.
463  Using Arduino / Project Guidance / Re: Advice on programming a accessory decoder for a computer controlle train layout. on: April 11, 2014, 02:10:57 pm
I suggest that you get in touch with MERG (Model Railway Electronics Group)
They designed DCC, so know much about it. There's some stuff on their homepage and there's a forum, but I think you have to be a member to use it.
464  Using Arduino / Microcontrollers / Re: Arduino Tre Price on: April 07, 2014, 09:17:51 pm
I never seem to get taxed for parcels from China. I have been taxed on a couple of high-value items from the USA.
UK Customs don't look at anything below about £15 (about US$25) as it's not cost effective to try to collect £3 ($5). The Post Office charges them that much to collect the payment on their behalf. Spanish Customs is probably the same.
Chinese shippers often mark the customs declaration for small items as 'gift'.
The most annoying thing is that Customs also tax the shipping charges. Your $211 shipping would become $253.20 here!
465  Using Arduino / General Electronics / Re: Thermo Electric Cooler/Heater. on: April 07, 2014, 08:10:45 pm
See these spring arms? They are made to work with the motor running so they drag away from the attachment point.

"Backwards" would be running in the other direction.
You're still calling the direction they (were designed to) run best in Forwards.
For a better motor with carbon brushes in holders with springs behind them, they can wear into a set. Or, as in the image below, they are made so they are angled and are meant to run in one direction.

I'm not saying that you can't run these in the other direction. I'm saying they may not work as well.
Agreed, when you use the terms 'one direction' and 'other direction'.
Pages: 1 ... 29 30 [31] 32 33 ... 102