Author Topic: More information on shields/kits?  (Read 5972 times)

Airith

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More information on shields/kits?
« on: August 23, 2012, 09:56:08 pm »
I'm completely new to Arduinos, I only have a programming background. I was hoping for an overview or at least a bit more information on:

1. Shields vs. kits
2. What each shield can be used for
3. What a beginner should be getting with a Digispark
4. Other tools/resources someone would need

Appreciate any info!
« Last Edit: August 23, 2012, 09:56:08 pm by Airith »

MichaelMeissner

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More information on shields/kits?
« Reply #1 on: August 23, 2012, 10:18:02 pm »
My stab at an answer until Eric chimes in:

A shield in the way it is specified on the backer page is just the board and some pins to connect the shield to the digispark.  So it is the outline of where to connect other pieces, but it doesn\'t give you the pieces.  You would have to buy them elsewhere.  For example, in the RGB shield, there are mounting holes for the tri-color LED and for the 3 resistors you need for the circuit.  You would need to source the LED and 3 resistors elsewhere.  With the kit, it includes the LED and 3 resistors.  Those of us who have Arduinos already likely have many of the parts, but if you are starting out new, you might not have the appropriate components.

More generally, in the Arduino world, a shield mounts on the Arduino, and does something or provides a more convenient way to wire up the circuit.  Some shields are pre-assembled, some require soldering.

Lets see, through hole, surface mount, grove, and breakout A/B are different ways to attach components to the digispark.  Through hole has holes that you put the component through and solder connections underneath.  Surface mount, you solder the item to the shield.  Breakout A/B has 3 pins (ground, 5v, signal) for each pin, which allows you to attach sensors or servos with common 3 pin wire attachments (the order of the 3 pins varys, hence the two different boards).  The grove shield uses a 4 wire connection popular with some components that can be easily plugged in.

The RGB shield/kit allows you to put a light that you can vary the color depending on the programming.

The infrared shield has an infrared receiver, and it allows you to signal the digispark with an infrared transmitter (like TV control) and it will do something.

The motor shield would allow you to connect one motor to the digispark.

The boost shield allows you to boost the power from a lower power power source to the digspark.

The MOSFET shield allows you to work with devices that have higher voltages I think, but I\'m not sure.

You will need to solder the parts to the shield, so you will need to get a soldering iron and solder.
« Last Edit: August 23, 2012, 10:19:51 pm by MichaelMeissner »

Airith

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More information on shields/kits?
« Reply #2 on: August 27, 2012, 05:01:05 pm »
Thanks for that Michael, here\'s what I\'m looking at so far (one of each unless stated):

stackable headers - What are these for?

boost shield kit - For batteries <7V I think

relay shield kit - Not sure

LCD I2C shield kit - Display screen

LED charlieplex shield kit - No idea

MOSFET shield kit - As you said, controlling power

motor shield kit - Controlling motors

2 Groove shield kit - These with the other Groove stuff sound perfect

infrared shield kit - Not sure

breakout shield b kit - What\'s the difference between this and A?

breakout shield a kit - See above

RGB shield kit - Control a light

thru hole proto shield PCB - No idea

surface mount proto shield PCB - No idea

EDIT:

2 Port Expander Shield Kits - Straightforward

EEPROM Shield Kits - Straightforward

RFM12B Shield PCB - Not sure

Is this over the top? Someone told me to get one of each thing, and since I haven\'t done anything Arduino related, I\'m getting the kits. I\'m hoping to avoid soldering (although I will if I have to), will the stackable headers let me do this?
« Last Edit: August 27, 2012, 07:17:41 pm by Airith »

MichaelMeissner

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More information on shields/kits?
« Reply #3 on: August 28, 2012, 05:25:16 am »
> Thanks for that Michael, here\'s what I\'m looking at so far (one of each unless stated):

Note, these are my speculations.  I am in no way connected to the Digispark/Digistump team, except being a kickstarter backer.

As I understand it, there are two guiding principals behind the design of the digispark, cost and size.  So they sacrifice generality for a shield that does one thing (and generally only one thing).  For example, a normal Arduino Uno is 2.7x2.1 inches with 20 programmable pins, while the digispark is 0.69x0.75 inches with 6 programmable pins.  So if you want flexibility go with the Uno (or the Mega if you need 70 pins), if you are doing a project that doesn\'t need that amount of flexibility go with the digispark.  As I\'ve mentioned before, I believe the original conception of the digispark was for people who had Arduinos already, and wanted to make a smaller project.

For generalized hacking where you are building something, and then tear it done to build the next thing, I would recommend getting a breadboard with power rails on either side.  The latest design of the digispark now allows you to pop the digispark directly into the breadboard, and then you wouldn\'t need to solder anything else.  Of course breadboards are much larger than a digispark, so you lose one of the two design aspects, but it gives you more flexibility when you are messing about.  You can pick up breadboards at various places, including Radio Shack in the USA.  For example: http://arduino-direct.com/sunshop/index.php?l=product_detail&p=168.  On my Uno, I\'ve gone to the Protoshield with micro breadboard, that doesn\'t have power rails, but it allows me to put a project on the board, and then take off the shield to switch to another project.

Here is a howto on breadboards: http://arduino-info.wikispaces.com/LowCostStarterSet-Connecting-Breadboarding

If you don\'t have prior Arduino or other embedded microprocessor, you might want to look around for the various starter kits for Arduino that include various jumper wires, leds, etc.  For example: http://arduino-direct.com/sunshop/index.php?l=product_detail&p=302

Note, the digisparks won\'t be available until November at the earliest, so if you are itching to get started now, I would suggest getting a cheap Uno or compatible kit, and then when the digispark arrives, you will be able to concentrate on electronics in the small.  If you are going the Arduino or compatible route, I would suggest buying from a company that has wikis and sample code for all of the products that they sell.  This is why I usually use links from yourduino.com (arduino-direct.com), because the owner has provided the tutorials, and on the arduino.cc forums, is generally helpful.  I bought my Uno starter kit from a giant electronics distributor who basically dumped everything into 1-2 plastic bags with no labels.

> stackable headers - What are these for?

In the Arduino world you can stack some shields on top of each other, and assuming each shield uses unique pins use the different features.  For example, you might have a shield that does ethernet or wifi networking, and put a LCD shield on top of that for the display.

> boost shield kit - For batteries <7V I think

Batteries less than 5 volts, such as coin batteries or 2 AAA batteries.  If your digispark is going to mostly be hooked to a 5v power source like a USB connection, you don\'t need this.  If you were going for something ultrasmall, you might need it.

> relay shield kit - Not sure

If you wanted your digispark to control the power to one device.  For example, you could use the relay shield to turn on/off a lamp that is normally plugged into the wall.

> LCD I2C shield kit - Display screen

If you want your device to print out information.  For debugging, you can print to the USB connection to your computer, but if you want a mobile device to print something out, you might want this.  However, note that you do lose some of the smallness of the digispark, due to the size of the screen.  However, you could mount the screen elsewhere.

> LED charlieplex shield kit - No idea

Charlieplexing is a technique where you can have an embedded processor control more lights than they have pins.  In this case, it is a grid of 4x5 lights.  If you want to do a light show, go with this.

> infrared shield kit - Not sure

This allows you to build a digispark that can be controlled by a remote infrared controller, such as used to turn TVs on/off.  This can be useful for a remote device.  Each IR device sends out a series of coded pulses that the digispark would figure out that you pressed the down arrow key on the controller.

> breakout shield b kit - What\'s the difference between this and A?
>  breakout shield a kit - See above

There are a bunch of sensors out there that use a common 3 wire connection, and you can just plug in this connection into the two breakout shields.  The 3 wires are ground, power, and signal, where the sensor uses the power and returns some amount of the power in the signal wire.  For digital sensors it just returns either no power or full power, but for analog signals, it returns a percentage (for example, a potentiometer is a rotary knob that returns different voltages depending on where you turn the dial).  You can also get things like servos (a type of motor that only goes from 0 to 180 degrees) that are programmed via the signal pin.  Unfortunately while there are 3 wires, not every device uses the same layout.  I think the more common encoding is breakout A (ground, 5 volt, signal), while breakout B (ground, signal, 5 volt) is less common.  I solved this by ordering one of each.

> RGB shield kit - Control a light

Control a light that has 3 different colors (normal LEDs are a single color).  The inspiration was another successful kickstart campaign of blink(1) that would sit plugged into a computer\'s USB connection, and it would turn different colors based on some condition.  Thus you could use it as a simple monitor.

> thru hole proto shield PCB - No idea

Advanced shield where you want to be able to mount components and then solder wires to the pins for connection.  Most of the other shields have connections in the board to connect a hole to the appropriate pin in the digispark.  In the through hole proto shield, you have to do this manually.  This is probably not the shield to use if you are starting out, though it gives more flexibility.

> surface mount proto shield PCB - No idea

If you don\'t do soldering, don\'t order this shield.  This is essentially a piece of plastic with metal patches.  You solder your component to the metal on the shield, and then solder a wire to connect the component to a pin.

> RFM12B Shield PCB - Not sure

I had to look this up, it is a radio communication device.  Unfortunately with the digispark, it uses 5 pins, which means it only has one pin available for a sensor or device.

> Is this over the top? Someone told me to get one of each thing, and since I haven\'t done anything Arduino related, I\'m getting the kits. I\'m hoping to avoid soldering (although I will if I have to), will the stackable headers let me do this?

See my comments above about breadboard, which in general allows you to avoid soldering.

I\'ve been delaying learning how to solder.  I have one of the learn to solder kits, but so far, I haven\'t taken the time to learn how to do it.

fraguada

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More information on shields/kits?
« Reply #4 on: August 28, 2012, 10:30:41 pm »
The RFM12b is pushing the limits of the digispark and would probably need some good testing and experimenting before it is simple to use for beginners.  I dove into the RFM12b with Jeelabs Jeenodes and that is why I am very happy that the digispark has a RFM12b shield.  I look forward to tweaking it and hopefully reducing the number of pins necessary...