This project based on Atmel AT89C52 and Dallas real-timeclock (RTC) chip DS12887 can be used to control and remotely program the switching operation of 24 electrically operated devices. The devices can be switched on/off at precise times repeatedly every day, every month. The microcontroller can be programmed for device control using a normal Phil
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ips TV remote control. The Philips IR format makes use of RC5 code, which is also known as bi-phase coding. ` In RC5-coded signals (Fig. 2), each bit has a uniform duration. A transition in the middle of the time interval assigned to each bit encodes its logical value (0` or 1`). A high-to-low transition assigns the bit a logic value of 0, ` and a low-to-high transition assigns the bit a logic value of 1. ` We need additional transitions at the beginning of each bit if a stream of equal bits is sent. However, there is no need of additional transitions if the The first two bits are start` bits, which are used to adjust and synchronise the receiver. These bits are used to calculate and analyse the bit length of the other bits. The third bit is a toggle` bit, which is toggled every time a button ispressed at the remote control. This bit is used to identify whether the button is really pressed or whether an obstacle came in between the IR path of the remote and the IR receiver. The five bits (A4 through A0) immediately following the toggle bit are used to identify the device (see Table III). So, a maximum of 32 devices can be identified to and respond individually to the same type of coding without any disturbance, i. e. , one among the 64 devices can be identified uniquely. Addresses of some of the remotes are shown in Table III. The six bits (C5 through C0) immediately following the five address bits are the control/command...
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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