BLOCK OVERVIEW

Overview

MakingThings' Blocks is a family of compatible electronic building blocks that provide the easiest and cheapest possible way to make simple interactive projects. Blocks offer an easy way to interpret and control the behavior of a wide range of electronic devices - sensors (light, motion, temperature, etc.) and actuators (motors, lights, fans, etc.). If you've ever wanted your lamp to turn on when you walk into a room, or a fan to turn on when it gets too hot, Blocks can help connect those devices and control their behavior.

There are several different kinds of Blocks. Some Blocks have preprogrammed functions to process the information from inputs and outputs. Some Blocks allow for the connection of devices with specific electrical requirements. Some Blocks are input or output devices. Browse the entire Blocks Range to explore the mix-and-match possibilities and create your own interactive project. Each Block has its own detailed Documentation and there is a detailed Glossary to help where technical terms are used.

To use Blocks, you need just a little electrical knowledge and an idea of what you want to achieve. Blocks all rely on simple screw terminals to make wire connections with the outside world. This enables people to buy and make their own sensors and actuators and simply screw them in with a screwdriver. No special connectors are required. This makes Blocks compatible with 1000's of electronic sensors and actuators and other devices already on the market. MakingThings also stocks a selection of sensors and actuators that come wired and ready to go.

We have tried to keep the amount of technical knowledge required to a minimum. However, we have outlined two areas - Power and Connections - that we feel are very important to the successful design and use of a Blocks project. By the time you've absorbed the information in these two sections, you'll have a grip on all the general technical knowledge needed to successfully work with Blocks.

Blocks are an ideal place to begin to learn about electronics, since many of the important features of electrical and electronic systems are present, but none of the things that require detailed study. This makes them ideal for quick designer-driver projects in the visual merchandising, museum exhibit, trade-show, special event and art areas, but also perfect for student, weekend hobbiest and parent-child projects. Blocks also provide a very smooth transition from beginner to expert level.

Blocks are 100% compatible with Teleo too, so when you do need to bring some value back into the computer, or need the computer to send some value you can easily do so.

As an introduction to what you can do with Blocks, here are some simple examples. They will help to convey an idea of what's possible.

Night Light

A night light provides illumination at night time for people moving around a house in the dark. The way people are detected is with a PIR sensor - also known as a motion sensor. This sensor outputs a short pulse whenever motion is detected. This project works by activating a halogen lamp for a period when the PIR sensor detects somebody nearby.

The Poly Block serves two purposes: using its Timer function, it extends the short "on" message from the PIR Sensor, to an interval of up to minutes. Halogen lamps draw more current than the normal outputs of the Poly Block can provide. Connecting the lamp to the Poly Block's switch output instead provides the high current switching capability the halogen lamp requires.

Also shown is a small value (0.1uF) capacitor across the lamp. Halogen lamps sometimes require this to reduce electrical noise they generate.

Temperature-controlled Fan

This example shows a fan that is controlled by a temperature sensor. The fan runs when the temperature exceeds a set amount. In this example it is assumed that the fan is capable of running off the +V power supply.

The Poly Block's compare function is being used to set the point at which the fan activates. The Compare function compares two voltages - one arriving on it's Input X input and the other on the Input Y input. The Input X value is being supplied by the temperature sensor. The Input Y value is being supplied by the Poly Block's trimpot. When the X value (from the temperature sensor) is greater than the Y value (from the trimpot), the Greater output is activated. This output is then connected to the Switch Block. Only one transistor is used on the Switch block. The Switch Blocks output is connected to the fan and will then turn the fan on when a "true" or 5V signal is sent to it. The fan can draw more than 10A of current when switched like this.

To calibrate the device correctly, adjust to the trimpot so the fan comes on when the appropriate temperature is reached.

If an AC Switch Block had been used instead of the Switch Block this same circuit could control the activation of a small AC fan.

Small fans, those requiring less than 2A, can be driven directly from the S1 output of the Poly Block and wouldn't therefore need the Switch Block at all. See the Auto Fan Cookbook recipe for more details.

Blocks Range

Poly Block		Provides 10 useful functions to control signal input and output including timers, switches, oscillators, adders, multipliers, and comparisons among others.
Servo Block		Controls the position of up to 4 hobby servo motors by incoming 0 - 5V analog signals.
Stepper Block		Control a stepper motor in one of two ways - either by specifying the speed and direction of the motor or by specifying its destination. In either case, control is provided by a mixture of analog and digital signals.
Line Block		Send digital and analog signals 100's of feet through only three wires. A fourth wire can be used to transmit power as well. Up to four sets of Line Blocks can utilize the same wires.
Switch Block		Allows small logic level signals to control large current devices. Can be used as simple on-off switches or as PWM switches. Control regular DC motors, lights or any DC device. Can control devices at more than 10A without additional heatsinking or cooling.
AC Switch		Permits the switching of AC devices up to 400VAC, drawing up to 16A. Control appliances that normally plug straight into a wall outlet.
Accelerometer Block		Provides two analog signals corresponding to the acceleration the block is experiencing on both the x-axis and y-axis. This sensor can therefore act as a tilt sensor in two directions.
Input Block		Provides two push buttons, four dip switches and two trimpots. These provide momentary digital signals, on-and-off style digital signals and analog signals respectively. Very helpful for testing and calibrating inputs.
LED Block		Provides four LEDs to monitor four separate digital outputs. The incoming signals are then passed through directly to the output connectors to be connected to other devices - the LED block contains it's own amplifier so the LED's don't interfere with the passage of the signals. Very helpful for testing outputs.
Potentiometer Block		The Potentiometer Block provides four analog outputs. The user can set the output value by adjusting the trimpots.
Breakout Block		Makes it very easy to connect four sensors that require their own power and ground, all from one +5V and 0V pair on a connected Block.
Regulator Block		The Regulator Block takes regulated or unregulated +V voltage and provides a regulated +5V supply at up to 1A of current. This is useful when more current is required than is normally available.
Power Connect Block		The Power Connect Block provides six identical connectors for the supply of power to a project. Power may be applied to any of the connectors and it becomes available at any of the others.

More Examples

Water level warning system

Use a Poly Block running the Compare function connected to a water probe consisting of two wires. Connect the Greater output of the Poly Block to a beeper or alarm of some kind.

Automatic Blind Lowerer

Use a Poly Block running the Compare function to compare the outside light levels to a threshold set by the Poly Block's trimpot. Take the Greater output of the Poly Block and pass it to the Position input of the Stepper Block. Connect the Stepper Block to a Stepper motor connected to the blind. Configure the Stepper Block so that it runs the blind from fully lowered to fully raised when it receives 5V and 0V respectively. Add a potentiometer to the Stepper block to control the Step rate.

Dark Activated Flashing Light

Use a Poly Block running the Compare function to compare light levels to a threshold set by the Poly Block's trimpot. Take the Greater output of the Poly Block and pass it to the Disable input of another Poly Block running the Oscillator function. Connect an LED or other kind of light to the output of the second Poly Block. Adjust the first Poly Block to trigger at the desired light level. Adjust the second Poly Block to flash the light at the desired frequency.

Event Timer

Connect a push button (the Start button) to the Trigger input on a Poly Block running the Timer function. Take the Time Expired output of that Poly Block and connected it to the Switch On function of a second Poly Block running the Switch function. Connect another push button (the Stop button) to the Switch Off input of the second Poly Block. Connect the Output of the second Poly Block to a Buzzer or some other indicator. Adjust the trimpot on the first Poly Block to get the time interval desired.

Powering Blocks

First off, all electronics need to be powered. All electronics are built around circuits, and the power supply provides the energy that makes the electricity flow around those circuits. There are many kinds of power supply: rechargable batteries, solar cells, AC-based wall transformers and so on. For these examples, we'll assume the use of a wall transformer.

Most Blocks require a regulated 5V supply. This can either be supplied to them directly or they can make it themselves from a larger unregulated supply if they have an on-board voltage regulator.

The simplest way to power a Block system is to use a block with a top power connector and regulator (like a Poly Block), as follows:

Here, the Block is being powered from a wall transformer power supply. This power supply must provide DC power in the range of 7V to 24V. When this arrives at the block, it is called +V and it is distributed to all the +V connectors on the board.

The power supply also provides another connection, 0V or Ground. This is the return path for electricity flowing into the system. It too is made available on all the connectors on the board called 0V.

If the Block has an on-board regulator, it takes the +V and 0V and uses them to make a steady 5V power supply. This too is sent to all the 5V connectors. Thus, a single power supply can distribute power to the whole system.

The power supply chosen must have sufficient capacity to power all the devices that will end up being connected to it. If, for example, you plan to have motors or halogen lights run off the power supply, you'll need a lot more power than if you're just running some LED's and a buzzer. Verify that the current consumed by all connected devices does not exceed the amperage provided by the power supply.

In order to reduce the likelihood of board damage, leave the power off until all the connections have been made and checked.

Connections

Once the power supply has been chosen for the board. It can be connected up to sensors, actuators and other blocks.

Physically, connections can be made with almost any kind of wire.

The basic principle is that the power supply provides the energy for the entire system to run. Each device receives power from the same power supply and shares the same 0V or Ground. The sending device (the one sending information to the other) connects to the receiving device via a single wire. This wire usually conveys a voltage from the sender to the receiver. In this case the fact that the two devices share the same reference voltage (0V) permits the voltage the Sender sends to be read accurately by the receiver.

There are three kinds of connections beyond power connections that you'll need to learn about. Digital, Analog and Switch.

Digital

Digital connections are connections that convey two values. One value often called "true", "on" or "1" is represented by 5V, the other value "false", "off" or "0" is often represented by 0V. Digital signals are mostly voltages with pretty meagre current supply capability. This means that you can't directly control anything beyond another digital device (and perhaps an LED or two) with it.

What these two values mean depends entirely on the context. If, for example the sensor is a motion detector, "0" might convey the fact that there is no motion present and "1" might convey the fact that there is motion. The receiving device might be a motor controller, where a digital signal of "1" might turn the motor on, and the signal of "0" might turn it off. Connecting them together would make a device where a motor runs when motion is detected in a room and is stopped when there is no motion in the room.

Notice that the two devices, the sending device and the receiving device, share a common 0V connection. This is so they both have the same point of reference. WIthout this, 5V to one device might be -5V to another. The +V connection has been omitted for simplicity - both devices are assumed to be powered.

Analog

Analog connections are connections that convey a range of values. The range of values are encoded into voltages between 0V and 5V. Like the digital signal, the analog signal is very feeble. It should only be connected to other electronic devices designed to receive an analog signal.

Just as with the Digital connections, what the analog value means is entirely context dependent. For example, an accelerometer might provide a 1V - 4V output depending on its orientation. 1V when tipped all the way over in one direction, 2.5V when held flat, and 4V when tipped all the way over the other direction. A dimmer block might take a 0V to 5V signal to determine how bright a light should be. If these two devices are connected together, the brightness of the light will be controlled by the orientation of the accelerometer.

Again, a common connection to 0V is required so that the two devices share a common reference point.

Switch

A switch connection is a little different from the other two, in that instead of a voltage being sent by a sending device and being read by a receiving device, the switch connects its output to 0V when it's on. This is useful when large devices need to be turned on and off. A switch output of some kind is necessary when switching anything that consumes more current than a logic-level electronic device or an LED.

When on, the Sending device permits electricity to flow from the ?V whatever that is (an arbitrary voltage), through the Device being switched and down to the 0V. When off, no current flows. Switching to 0V might seem a little upside down, why not have the Sending device just output +V when the switch is on?

There is a mundane electronic reason for doing it the other way around which is that the electronic switches people often use (MOSFET's) work best switching to 0V, but the best reason is that switching to ground lets us use any voltage we like. As long as the power supplies share the same 0V connection, any voltage (between 0V and 30V) can be used.

PWM

PWM stands for Pulse-Width Modulation and is an electronic technique for creating analog outputs. It is mentioned here because it relates to all three of the connections above.

It works as follows. A digital signal is produced which turns on and off very rapidly (7000 times a second or more). The length of the on pulse can be varied from never turning on, through being on for half the time all the way up to being on for the whole time.

An analog signal is created from this by averaging out the signal with a low pass filter. When the on-time is 0%, the corresponding voltage is 0V. When the on-time is 50%, the voltage will be 2.5V, when the on time is 100%, the voltage will be 5V.

This analog signal can be used anytime an analog signal is required and where the receipient of the signal will not draw much more current than milliamps.

It turns out that creating voltages for running higher current devices like motors, and larger lights is quite difficult. Here PWM helps again. By connecting a PWM signal to a Switch ouput large motors and lights can be controlled very easily.

Several Blocks, such as the Poly Block, have versatile outputs that can output analog signals, digital signals and switch outputs all from the same command. Its Output 0 has three different connection points: The Digital output which outputs 0V - 5V will output either straight digital output signals (i.e. on and off) or PWM signals, neither of which can control larger loads. The Analog output produces an analog voltage from the Digital output. If this output happens to be a PWM signal, then the Analog output will be a voltage corresponding to that PWM signal. Finally, for switching higher loads, the Switch output takes that same Digital signal and provides synchronized switching to 0V. This permits the control of larger devices than the digital version.

Advanced Powering Blocks

Blocks can be powered in a number of ways. Blocks have three power connections: +V, 0V and 5V. These appear as terminals on many of the connectors. In general, all the connectors with the same names (i.e. +V, 0V and 5V) are all connected together on a Block (Fig. 1), so you can supply power on any one set of them and expect that power to be present on all of them.

Fig. 1

Power can therefore come from any side:

Fig. 2

When two or more Blocks with regulators are being used, their 5V lines should not be connected (Fig.3). Each Block will create its own 5V and if connected their regulators would interfere with each other.

Fig. 3

If there is a good supply of regulated 5V (Fig. 4), all the on-board regulators can be by-passed by supplying then 5V directly and leaving the V+ unconnected. A reason for doing this might be that you have a very efficient 5V regulator or converter of some kind and you are running off a battery. This scheme would deliver the 5V power more efficiently than the regulators on the boards might. The 5V supply would have to have sufficient current capacity to be able to provide power for everything that is connected. A drawback to doing this is that every source of electrical noise connected to the power lines will tend to be passed to every other Block. When each block is generating it's own power, the likelihood of this happening is reduced.

Fig. 4