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Breadboards are a useful tool for prototyping circuits.
Breadboard comprises of a grid of holes, with collections of holes electrically connected. Integrated circuits (dual in-line packages/DIP), leaded components (e.g. LED's, capacitors, resistors), connectors and wires can be inserted in to the holes, enabling circuit prototypes to be built without the need for soldering.
The diagram below shows the standard connections of a breadboard. All the rows of 5 holes are connected, but not across the central gap, and all the holes in the 4 colums are connected.
The default breadboard setup used in our examples places the mbed Microcontroller at the top-center of the breadboard with the USB connector towards the edge.
Wires connect GND (pin 1) to the left vertical rail, and VOUT (pin 40) to the right vertical rail. This gives us 0v and 3.3v power rails on the left and right of the board, making the common task of wiring to power rails easy.
Note: The mbed Microcontroller is fragile, and inserting it in to breadboard will require some force; ensure you line up the holes, then press evenly until it goes in to the board fully.
Never try and remove the mbed Microcontroller by pulling on the USB lead or USB connector
You'll just pull off the connector itself!
It is best to leave the mbed Microcontroller in the board whenever possible; if you do need to remove it, be patient and do it carefully. Use a small jewelers screwdriver or similar, and lever it a bit at a time from each of the four corners in turn, ensuring you pull up with the screwdriver so you are pressing against the breadboard with the tip and the edge of the microcontroller with the shaft, rather than the tip touching the bottom of the microcontroller (which might damage the components on the underside).
So remember..
If know you are going to work with servos, motors or other devices in projects that would need more then 460MA, you might consider one of the larger breadboards that has banana jack power connections as seen below. Then take an AC to DC wall adapter (likely would want about 5VDC at 1-2A) and put banana plugs on it to plug into the breadboard for extra power. You might even have an AC adapter around already that you are not using. Since you cut off the strange power jack, most will work just fine. Be sure to check the wires with a voltmeter and color code the banana plug so that you always connect 5 to red and black to GND. A banana plug connector is also shown below. Many of them use screw connections, so soldering is not required. We found some small AC to DC wall adapters with a switching regulator at Digikey for $20 that put out 5V at 4A.
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On longer breadboard strips the lengthwise sidebars may have a larger gap between holes about halfway along the strip. This may indicate that the lengthwise connectins stop there. That can cause problems if you have devices plugged in further down and think you have connected them to your 3V and GND rails. If you see such a longer gap, stick a pin into the rail above and below the gap and measure resistance. If it is high, you have to put a jumper over the gap.
Of course you can also potentially use the longer gap for lengthening a bus such as the I2C bus to connect multiple devices, but then you must remove those jumpers to GND and 3.3V (and as a side remark, the SDA and SCL lines need pull up resistors to 3.3 V or else they may not work very well).
Above it is suggested to have 3.3V and GND on both lengthwise side panels. As there are still quite a number of 5V devices around, I find it more conevenient to have GND and 5V on one side, and 3.3V and GND on the other side. Just make sure you clearly mark what voltage sits on which side in such a hybrid setup.