CN106911334A - A kind of fire-fighting industrial bus coding method - Google Patents

Abstract

The invention discloses a kind of fire-fighting industrial bus coding method, including：(1) fire alarm control unit is encoded using the low level pulse that dutycycle is less than 0.3 as bit demal starting point, and synchronizing signal；(2) when encoding, bit " 0 " is determined with the pulse width between level trailing edge twice, bit " 1 " is determined with the pulse width between level rising edge twice；Per two ends trailing edge an independent synchronizing signal is assigned in coding；(3) repeat step (2) continuous programming code, until coding is completed, then by bus to intelligent parts signaling.Flow of the present invention is simple, coded system is easy, can be while data transfer accuracy is ensured, it is to avoid bus-free time problem more long, therefore, the present invention is suitable to popularization and application.

Description

A kind of fire-fighting industrial bus coding method

Technical field

The present invention relates to technical field of fire control, and in particular to be a kind of fire-fighting industrial bus coding method.

Background technology

Existing fire alarm control system, when signaling is carried out using bus, controller main frame need to be first in low Level state is drawn high, and when main frame sends burst of data, such as when " 00101 ", the start bit of information transfer is a data, often The time of a data transmission is fixed, so the time of transmission burst of data is also fixed value.This coded system, passes in information Due to it is possible that the phenomenon that is advanced or delayed of clock in defeated process, thus during coding, will be because of in transmission first Error being generated during data and promoting whole data encoding processor to form cumulative errors, it is incorrect to ultimately cause coding, reduces Communication two ends clock it is accurate, and then by the low accuracy of data transfer, the verification of follow-up data can also be produced larger Influence.

For these reasons, at present, the accuracy of data when some producers are in order to ensure to encode, reduces because clock institute band The accumulated error come, using Synchronization (such as the technology disclosed in Patent No. 02129002.4), will divide the time Equally spaced segment, each of which section represents a bit.Each short time dimidiation again in itself, preceding half time passed Signal is the radix-minus-one complement that the time period transmits bit value, afterwards the transmission of half time period be bit value in itself.Although this mode exists When level changes, there is synchronizing signal to produce, so that because of the brought error that is retarded or advanced of clock when reducing coding, but In each level period of change, because free time is more long, thus capacity to exterior part electric capacity can have higher requirements, hardware Acquisition cost is higher；Meanwhile, the load capacity of bus can also be deteriorated, and cause its power supply and driving force to rear end equipment to be dropped It is low.

The content of the invention

For the deficiency of above-mentioned technology, the invention provides a kind of fire-fighting industrial bus coding method, data can ensured While transmission accuracy, it is to avoid bus-free time problem more long.

To achieve the above object, the technical solution adopted by the present invention is as follows：

A kind of fire-fighting industrial bus coding method, comprises the following steps：

(1) fire alarm control unit is using low level pulse that dutycycle is less than 0.3 as bit demal starting point Encoded, and synchronizing signal；

(2) when encoding, bit " 0 " is determined with the pulse width between level trailing edge twice, is risen with level twice Pulse width between determines bit " 1 "；Decline to grind per two ends and assign an independent synchronizing signal in coding；

(3) repeat step (2) continuous programming code, until coding is completed, then by bus to intelligent parts signaling.

Further, in the step (2), pulse width when determining bit " 1 " is to determine arteries and veins during bit " 0 " Fill the twice of width.

Compared with prior art, the invention has the advantages that：

(1) present invention is using a low level pulse width for dutycycle minimum (less than 0.3) as bit demal starting point Encoded, and with synchronizing signal, because low level pulse width is far smaller than high level, thus bus when reducing coding The upper idle time, power supply and the driving force of external portion's equipment were both can ensure that, while also reducing to exterior part capacitance Requirement, reduce the cost that hardware is purchased.

(2) present invention determines bit " 0 " and " 1 " with the pulse width twice between level trailing edge or rising edge, and A separate synchronizing signal is assigned simultaneously, consequently, it is possible to for comparing the mode of Synchronization, the present invention is not only Coded system is easy, flow is simple, and equally can ensure that the accuracy of data transfer.

(3) present invention it is all linked with one another, be closely connected, its be fire-fighting industrial bus high efficiency coding and data transfer provide Ensure, therefore, the present invention is suitable to the popularization and application in technical field of fire control.

Brief description of the drawings

Fig. 1 is schematic flow sheet of the invention.

Fig. 2 is pulse schematic diagram.

Specific embodiment

The invention will be further described with embodiment for explanation below in conjunction with the accompanying drawings, and mode of the invention includes but not only limits In following examples.

As shown in Figure 1, 2, the invention provides a kind of efficient bus code method, both may insure data transfer Accuracy, can avoid bus-free time long and cause load capacity to be deteriorated again.Main flow of the invention is as follows：

First, the low level pulse using a dutycycle minimum (less than 0.3) is encoded as bit demal starting point, And synchronizing signal.During coding, with the pulse width between level trailing edge twice determine bit " 0 " (pulse width as 400~ 500 μ s, comprising a low level pulse width of 50~100 μ s), ratio is determined with the pulse width between level rising edge twice Special position " 1 " (twice of pulse width when pulse width is to determine bit " 0 ", and it is equally wide comprising a low level pulse Degree), the signal of rising edge and trailing edge is as shown in Figure 2.Also, in the present embodiment, assigned in coding per two ends trailing edge One independent synchronizing signal, causes coding cumulative errors occur to avoid clock from being advanced or delayed.

In the manner described above, controller continuous programming code, until coding is completed, then by bus to intelligent parts signaling.

The present invention effectively improves the accuracy of fire-fighting industrial bus data transfer by rational software and hardware combining, And ensure that to the power supply of external equipment and driving force and reduce hardware acquisition cost.Therefore, the present invention is well by work The skill upgrading of industry bus code to a new height, its compared with prior art, with prominent substantive distinguishing features and aobvious The progress of work.

Above-described embodiment is only one of the preferred embodiment of the present invention, should not be taken to limit protection model of the invention Enclose, it is all body design thought of the invention and mentally make have no the change of essential meaning or polishing, what it was solved Technical problem is still consistent with the present invention, should be included within protection scope of the present invention.

Claims (2)

1. a kind of fire-fighting industrial bus coding method, it is characterised in that comprise the following steps：

(1) fire alarm control unit is carried out using the low level pulse that dutycycle is less than 0.3 as bit demal starting point Coding, and synchronizing signal；

(2) encode when, bit " 0 " is determined with the pulse width between level trailing edge twice, with level rising edge twice it Between pulse width determine bit " 1 "；Decline to grind per two ends and assign an independent synchronizing signal in coding；

(3) repeat step (2) continuous programming code, until coding is completed, then by bus to intelligent parts signaling.

2. a kind of fire-fighting industrial bus coding method according to claim 1, it is characterised in that in the step (2), really Arteries and veins when pulse width when determining bit " 1 " is to determine bit " 0 " fills the twice of width.