CN2133988Y

CN2133988Y - Programmable square wave generator

Info

Publication number: CN2133988Y
Application number: CN 92218039
Authority: CN
Inventors: 崔群; 吴进进; 洪平
Original assignee: ANHUI WUHU INSTRUMENTATION RESEARCH INSTITUTE
Current assignee: ANHUI WUHU INSTRUMENTATION RESEARCH INSTITUTE
Priority date: 1992-06-06
Filing date: 1992-06-06
Publication date: 1993-05-19
Anticipated expiration: 2002-06-06

Abstract

The utility model discloses a programmable square wave generator. The programmable square wave generator is composed of an SCM control system unit, an oscillating source unit, a frequency dividing circuit unit, an interface circuit unit and an amplifying circuit unit, wherein, a 74LS90, a 74LS92, a 74LS00 and a 74LS10 form the frequency dividing circuit and send out frequency signals toward the oscillating source unit. Three paths of signals with different frequencies are produced through frequency dividing and are connected to the port 8031P< 1 > of an SCM through the 74LS00, the 74LS10 and an NOT gate. The frequency dividing circuit, the timer in programmable interface chip 8155, TIMER/in and TIMER/out form a square wave generator under the control of the SCM 8031. The utility model has the advantages of simple structure, high stability, large frequency width from 1 to 9999Hz, high given value precision which is plus minus 1/1000, etc.

Description

Programmable square wave generator

The utility model belongs to the application of singlechip technology, refers more particularly to high accuracy wideband square-wave generator able to programme.

At present, in a series of high accuracy wideband square-wave generators able to programme, its output square waveform technical scheme has many types, such as having by RC oscillator mode, utilize phase-locked loop manner, the direct mode that produces of the delivery outlet that adopts microcomputer is also arranged, yet in the prior art, though scheme is different, all exist a common weak part, circuit structure more complicated that Here it is, form after the product, small product size is bigger, can only exist with desk-top or cabinet type structure apperance usually, for needing under some specified conditions above square-wave generator circuit product is carried, obviously, product of the prior art then can not satisfy the real work needs.

The purpose of this utility model is: at above weak point, provide a kind of improvement project, simplified circuit structure greatly, can provide a kind of integrated level height by the difference requirement, function is strong, and the high accuracy wideband square wave electric organ able to programme that price is low is with the renewal product as prior art.

The technical solution of the utility model be achieved in that select 8031 for use, four integrated packages of 74LS373,2764,2816A, and resistance capacitor device of other relevant coupling is formed single-chip computer control system unit; Select the resistance of 74HC04 and relevant coupling, the oscillation source unit that capacitor is formed a 6MHZ frequency for use; Select for use 74LS90,74LS92,74LS00,74LS10 integrated package to form the frequency dividing circuit unit; Select 8155 for use, 74LS249,74LS145 and 9 LED show forms the interface microcontroller circuit units with 20 ML-3 buttons, and amplifier circuit unit constitutes high accuracy wideband square-wave generator able to programme.When the signal of oscillation source unit generation 6MHZ frequency, by integrated package 74LS92, to be divided into 1/12 of original signal frequency, it is the frequency signal of 500KHZ, and this signal is again by integrated package 74LS90 frequency division, produce the signal of primary frequency 1/5, be 100KHZ, therefore this frequency dividing circuit unit will have three the tunnel to be respectively 6MHZ, 500KHZ, a 100KHZ frequency signal end with two input NAND gate 74LS00 by being attached thereto respectively, and the other end of 74LS00 is then received the P of single-chip microcomputer 8031 ₁Mouthful, cause each NAND gate to have no signal output then to be decided by single-chip microcomputer 8031P ₁The control of mouth, three NAND gate at a time, only have an output signal under the control of single-chip microcomputer, and two then do not have output signal in addition, are high level; The output of three NAND gate is received a NAND gate 74LS10 with three inputs again, and the output of this NAND gate is received the frequency input signal of 8155 TIMER/in end as 8155 timers.Utilize the timer and TIMER/in, the TIMER/out end of 8155 programmable interface chips itself to constitute a waveform generator, thereby produce the square-wave signal of required frequency, the amplifying circuit of forming by 3DG12 and relevant resistance device, mainly the amplitude leyel with output signal is converted to desirable value, has increased load capacity simultaneously greatly.

Compared with prior art, the utility model structure is especially simple, can produce the 1-9999HZ frequency with fine stability, and its set point precision can reach ± and 1/1000, apparatus can carry with the individual, and its cost cost is obviously than the obvious reduction of like product.

Accompanying drawing is that the utility model is applied in automobile, motorcycle, electronic tachometer check meter embodiment schematic diagram.

Again the utility model is elaborated below in conjunction with accompanying drawing.

As shown in the figure, oscillation source unit 1 produces through vibration and the signal of output 6MHZ frequency input control system unit 2 and frequency dividing circuit unit 3 respectively, when the 6MHZ signal by integrated package 74LS92, being divided into original signal frequency 1/12 is 500KHZ; By integrated package 74LS90, being divided into original signal frequency 1/5 is 100KHZ again, and three road frequency signals are connected to NAND gate 74L,S00 one end with two inputs, and the 74LS00 other end is connected in the P of single-chip microcomputer 8031 ₁Mouthful, the output of 74LS00 is connected to a NAND gate 74LS10 with three inputs respectively, the 74LS10 output is connected in the TIMER/in end of programmable interface chip 8155 in the interface microcontroller circuit unit 4, with frequency input signal as 8155 timers, timer and TIMER/in by frequency dividing circuit unit 3 and 8155 programmable interface cores electricity itself, the waveform generator that the TIMER/out end constitutes under single-chip microcomputer 8031 controls produces the square-wave signal of required frequency, amplify through amplifier circuit unit 5, with the amplitude output signal level conversion to desirable value.

Claims

1, a kind of programmable square wave generator is made up of monolithic sheet machine input control system unit 2, frequency dividing circuit unit 3, interface microcontroller circuit unit 4, hunting of frequency source unit 1 and amplifier circuit unit 5, it is characterized in that:

(1) oscillation source unit 1 output frequency signal, through forming frequency dividing circuit unit 3 by 74LS90,74LS92,74LS00,74LS10, frequency division produces the different frequency signal of three tunnel frequencies, is connected in the P that three other ends with three 74LS00 of two input NAND gate are received single-chip microcomputer 8031 ₁Mouthful, the output of three 74LS10 joins with a NAND gate 74LS10 input with three inputs respectively, and the output of 74LS10 and 8155 TIMER/in join;

(2) in frequency dividing circuit unit 3 and the programmable interface chip 8155 regularly and TIMER/in, TIMER/out under single-chip microcomputer 8031 controls, constitute side waveform generator.