This is a high-speed control scheme LED display screen circuit theory. Adopt the MCS51 series one-chip computer to control LED display screen; The random access memory 62512 is used as the data storage of LED display screen, store the matrix data waiting to reveal the content; Adopt 8 lines of scanning modes, the dot matrix of lamellar LED is a
Click here to download the full size of the above Circuit.
scene of sharing and a group driving circuit; Each slice of LED dot matrix slice has a series of lines of driving circuit, use 74LS377 As listing the latch that is driven, CPU writes the matrix data to the latch which lists the driving circuit through the parallel bus; The decoder circuit of the address, used for producing LED dot matrix slice walking driving circuit and chip selection address which lists the driving circuit. There are two characteristics of this scheme: First, though CPU still gives and lists the latch of the driving circuit and writes the matrix data through the parallel bus, but the latching the control signal RD that the signal uses CPU instead, but not WR of the regular usage of the latch; Second, address decoder circuit guaranteed LED dot matrix a chip selection address which lists the driving circuit and logic address of some segment of the data storage are eclipsed, but not regular usage, these two group addresses must be separated. Because above-mentioned some of circuit change briefly, one-chip computer take place obvious change to the intersection of LED and the intersection of presentation control and efficiency of display screen. The concrete working phase is as follows: Having already packed into the address of the data storage while assuming the indicator DPTR of the data, execute instruction MOVXA, @DPTR . The function of this order is CPU, according to pointing to reading the matrix data...
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.....
characters left:
emin May 12, 2019