It can detect what`s being typed on it. It can be used to send text to and/or receive text from a computer via USB. It was designed as a platform for playing interactive fiction games, in particular to play custom software being developed for it by Jim Munroe. As always, I hope to one day flesh this explanation out more, but since this is awork in progress, this will have to do for now. One important note,
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of which I am (unduly) proud: no permanent modifications have been made to the typewriter. This might be important if, in the future, I use a typewriter that I care about better preserving. Each key is attached by fishing line to a solenoid, an electromechanical device that pulls down when electric current is passed through it. The solenoids sit behind and underneath the typewriter in a multi-layer structure. The solenoids are connected to a MOSFET, which allows the lower-power parts of the circuit to control the high-power solenoids. The MOSFETs are connected in sets of eight to shift registers (integrated circuits that can, amongst other things, expand the number of outputs on a microcontroller). The shift registers are connected to an Arduino, which is connected to a computer via USB. When the computer sends a character to the Arduino, the Arduino chooses which solenoid to fire and sends that information to the shift registers. Detecting when a key is pressed uses a method very similar to that used by the USB Typewriter : a series of flattened resistors are placed such that when a typewriter key is pressed, the mechanism makes contact. The mechanism has been grounded to our electrical circuit to enable detection. Shift registers are used again here, this to to expand the number of inputs rather than the outputs. When the Arduino detects a contact, it sends the appropriate character to the computer via USB. It`s acting as...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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