CN102523003B - Time-sharing multiplexing keyboard display scanning circuit applied to fire alarm controller - Google Patents
Time-sharing multiplexing keyboard display scanning circuit applied to fire alarm controller Download PDFInfo
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- CN102523003B CN102523003B CN201110421160.XA CN201110421160A CN102523003B CN 102523003 B CN102523003 B CN 102523003B CN 201110421160 A CN201110421160 A CN 201110421160A CN 102523003 B CN102523003 B CN 102523003B
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Abstract
The invention discloses a time-sharing multiplexing keyboard display scanning circuit applied to a fire alarm controller. The circuit comprises a master control circuit, a keyboard scanning circuit, a display scanning circuit and a communication circuit. And the keyboard scanning circuit, the display scanning circuit and the communication circuit are connected with the master control circuit. According to the invention, the time-sharing multiplexing keyboard display scanning circuit applied to a fire alarm controller has characteristics of simple using method, small volume, low cost, and few occupied CPU resources and the like.
Description
Technical field
The present invention relates to a kind of time-sharing multiplex keyboard reading scan circuit for fire alarm control unit.
Background technology
Along with the high speed development of national economy, the scale of building is increasingly huge, and automatic fire alarm system is gradually complicated, needs the interlocking equipment of controlling also to get more and more in system.In order to ensure equipment reliability service, generally all in Fire Autoalarm, establish a button and two status indicator lamps are set respectively each interlock, button is used for controlling its startup and stops, and indicator light is used to indicate equipment state.In large-sized fire automatic alarm system, this type of button can reach thousands of, and indicator light is more up to 1,000.
The keyboard-display circuit that Fire Autoalarm adopts now mainly contains two kinds: and shape of the mouth as one speaks special chip and serial ports type special chip.And shape of the mouth as one speaks special chip is as INTEL 8279 circuit, this circuit usage is simple, but circuit own vol is large, take CPU hardware resource more, and periphery also needs to have the interlock circuit such as decoder, driver cooperating, whole circuit implements more numerous and more jumbled, take up room large, cost is high.Serial ports type special chip is as circuit such as BC7291, ZLG7290, circuit usage complexity, and software code amount is large, take cpu resource more, and periphery also needs to have the circuit such as shift register, driver cooperating, whole circuit implements more numerous and more jumbled, take up room large, cost is high.
Summary of the invention
The present invention is the weak point existing in above-mentioned prior art for avoiding, and a kind of time-sharing multiplex keyboard reading scan circuit for fire alarm control unit is provided, and takies that cpu resource is many, the large and high in cost of production problem of volume to solve existing keyboard-display circuit.
The present invention be technical solution problem by the following technical solutions.
For the time-sharing multiplex keyboard reading scan circuit of fire alarm control unit, its design feature is to comprise governor circuit, keyboard scanning circuit, reading scan circuit and telecommunication circuit; Described keyboard scanning circuit, reading scan circuit and telecommunication circuit are all connected with described governor circuit;
Keyboard scanning circuit, for obtaining the keyboard signal of pressing and upspring, and sends the signal of acquisition to governor circuit;
Reading scan circuit, for obtaining the control signal of governor circuit, and according to the switch of this control signal control LED light;
Telecommunication circuit, for communicating by letter between governor circuit and host computer, receives the outside demonstration information that host computer sends, and the button value detecting is sent to host computer;
Governor circuit, the signal sending for receiving keyboard scanning circuit, reading scan circuit and telecommunication circuit, and the control signal of generation is sent to keyboard scanning circuit, reading scan circuit and telecommunication circuit.
The design feature of the time-sharing multiplex keyboard reading scan circuit for fire alarm control unit of the present invention is also:
Described governor circuit comprises single-chip microcomputer D1, resistance R 5～R12, resistance R 18, capacitor C 7, capacitor C 8, capacitor C 10, crystal G1 and address wire jumper X3; Described capacitor C 7, capacitor C 8 and a clock oscillation circuit of crystal G1 composition, for single-chip microcomputer, D1 provides clock signal; Resistance R 18 and capacitor C 10 form an electrify restoration circuit, for single-chip microcomputer provides reset signal; Address wire jumper X3 is for configuring the mailing address of governor circuit; Resistance R 5～R12 forms a pull-up circuit, for strengthening the P0 mouth driving force of single-chip microcomputer D1; Single-chip microcomputer D1, by P0 mouth, P1 mouth, P2 mouth supervisory keyboard scanning circuit and reading scan circuit, realizes the function of supervisory keyboard matrix and LED matrix.
Described keyboard scanning circuit comprises resistance R 16～R23, resistance R 43～R50, diode V128～V135, bus driver D3, bus driver D4 and keyboard matrix S0～S63; Bus driver D3, D4 and reading scan circuit share.Resistance R 16～R23 is pull down resistor, for determining that what single-chip microcomputer D1 read by P0 mouth is all low level not when being pressed; Resistance R 16～R23 also forms a bleeder circuit with resistance R 43～R50, and its voltage ratio guarantees that, in the time having key to be pressed, what single-chip microcomputer D1 read is high level; Diode V128～V135 forms an anti-button short circuit current, in the time that two keys of same row are pressed simultaneously, prevents the horizontal scanning line short circuit that it is corresponding; Bus driver D3 time-sharing work is under two states: input and output, and the switching of its working method is controlled by single-chip microcomputer D1; In the keyboard scan period, bus driver D3 works in input state, and single-chip microcomputer D1 is by the line scan signals of bus driver D4 output key, and by bus driver, D3 reads key-press status; 64 button S0～S63 are arranged in 8 buttons of every row, and one has 8 row, form the keyboard matrix of 8 × 8.
Described reading scan circuit comprises resistance R 27～R42, bus driver D3, bus driver D4, bus driver D5 and LED matrix; Wherein bus driver D3, D4 and keyboard scanning circuit share.Resistance R 27～R42 is 16 current-limiting resistances, and the electric current while lighting for limiting LED prevents that bus driver is because of the excessive damage of electric current; Bus driver D3 works in output state in the reading scan period, and B0～B7 pin of bus driver D3 is exported high level successively, circulates 2 times; Bus driver D4 and bus driver D5 output information code successively, when bus driver D4 output information code, bus driver D5 output is high level entirely, and bus driver D5 is output information code successively, and bus driver D4 output is high level entirely; 128 LED light are arranged in 8 LED light of every row, and one has 16 row, form the LED matrix of 16 × 8.
Described telecommunication circuit comprises resistance R 1～R4, serial ports transceiver D2, connector X1, jumper wire device X5; Serial ports transceiver D2 is for the transmitting-receiving of serial data and the conversion of data level; Resistance R 1 is a pull-up resistor, serial ports transceiver D2 /RE in low level state, makes serial ports transceiver D2 be operated in accepting state while holding level with both hands; In the time that needs send data, serial ports transceiver D2 /RE end will transfer high level state to, and pull-up resistor R1 can provide pulling drive electric current, accelerates the switching of serial ports transceiver operating state; Resistance R 2 and resistance R 3 are two current-limiting resistances, for preventing that order wire short circuit from burning out serial ports transceiver; Resistance R 4, jumper wire device X5 are that a terminal build-out resistor is selected circuit, for signal transmssion line coupling, prevent signal reflex.
Compared with the prior art, beneficial effect of the present invention is embodied in:
Time-sharing multiplex keyboard reading scan circuit of the present invention, comprises governor circuit, keyboard scanning circuit, reading scan circuit and telecommunication circuit.Governor circuit is connected with keyboard scanning circuit, manages 64 buttons, realizes and judges that button presses, upsprings and button shake removal function; Governor circuit is connected with reading scan circuit, manages 128 LED light, realizes switch LED light function; Governor circuit is connected with telecommunication circuit, completes and receives outside demonstration information, sends button value function.Time-sharing multiplex keyboard reading scan circuit of the present invention, possesses the function of simultaneously managing 64 buttons and 128 LED light or 16 8 charactrons, has that usage is simple, volume is little, cost is low, takies the features such as cpu resource is few.
Brief description of the drawings
Fig. 1 is the theory diagram of time-sharing multiplex keyboard reading scan circuit of the present invention.
Fig. 2 is the structure chart of the governor circuit of time-sharing multiplex keyboard reading scan circuit of the present invention.
Fig. 3 and Fig. 4 are the keyboard scanning circuit of time-sharing multiplex keyboard reading scan circuit of the present invention and the structure chart of reading scan circuit.
Fig. 5 is the structure chart of the telecommunication circuit of time-sharing multiplex keyboard reading scan circuit of the present invention.
Below pass through embodiment, and the invention will be further described by reference to the accompanying drawings.
Embodiment
Referring to Fig. 1, for the time-sharing multiplex keyboard reading scan circuit of fire alarm control unit, comprise governor circuit, keyboard scanning circuit, reading scan circuit and telecommunication circuit; Described keyboard scanning circuit, reading scan circuit and telecommunication circuit are all connected with described governor circuit;
Keyboard scanning circuit, for obtaining the keyboard signal of pressing and upspring, and sends the signal of acquisition to governor circuit;
Reading scan circuit, for obtaining the control signal of governor circuit, and according to the switch of this control signal control LED light;
Telecommunication circuit, for communicating by letter between governor circuit and host computer, receives the outside demonstration information that host computer sends, and the button value detecting is sent to host computer;
Governor circuit, the signal sending for receiving keyboard scanning circuit, reading scan circuit and telecommunication circuit, and the control signal of generation is sent to keyboard scanning circuit, reading scan circuit and telecommunication circuit.
As Fig. 2, described governor circuit comprises single-chip microcomputer D1, resistance R 5～R12, resistance R 18, capacitor C 7, capacitor C 8, capacitor C 10, crystal G1 and address wire jumper X3; Described capacitor C 7, capacitor C 8 and a clock oscillation circuit of crystal G1 composition, for single-chip microcomputer, D1 provides clock signal; Resistance R 18 and capacitor C 10 form an electrify restoration circuit, for single-chip microcomputer provides reset signal; Address wire jumper X3 is for configuring the mailing address of governor circuit; Resistance R 5～R12 forms a pull-up circuit, for strengthening the P0 mouth driving force of single-chip microcomputer D1; Single-chip microcomputer D1, by P0 mouth, P1 mouth, P2 mouth supervisory keyboard scanning circuit and reading scan circuit, realizes the function of supervisory keyboard matrix and LED matrix.
As Fig. 3 and Fig. 4, described keyboard scanning circuit comprises resistance R 16～R23, resistance R 43～R50, diode V128～V135, bus driver D3, bus driver D4 and keyboard matrix S0～S63; Bus driver D3, D4 and reading scan circuit share.Resistance R 16～R23 is pull down resistor, for determining that what single-chip microcomputer D1 read by P0 mouth is all low level not when being pressed; Resistance R 16～R23 also forms a bleeder circuit with resistance R 43～R50, and its voltage ratio guarantees that, in the time having key to be pressed, what single-chip microcomputer D1 read is high level; Diode V128～V135 forms an anti-button short circuit current, in the time that two keys of same row are pressed simultaneously, prevents the horizontal scanning line short circuit that it is corresponding; Bus driver D3 time-sharing work is under two states: input and output, and the switching of its working method is controlled by single-chip microcomputer D1; In the keyboard scan period, bus driver D3 works in input state, and single-chip microcomputer D1 is by the line scan signals of bus driver D4 output key, and by bus driver, D3 reads key-press status; 64 button S0～S63 are arranged in 8 buttons of every row, and one has 8 row, form the keyboard matrix of 8 × 8.
As Fig. 3 and Fig. 4, described reading scan circuit comprises resistance R 27～R42, bus driver D3, bus driver D4, bus driver D5 and LED matrix; Wherein bus driver D3, D4 and keyboard scanning circuit share.Resistance R 27～R42 is 16 current-limiting resistances, and the electric current while lighting for limiting LED prevents that bus driver is because of the excessive damage of electric current; Bus driver D3 works in output state in the reading scan period, and B0～B7 pin of bus driver D3 is exported high level successively, circulates 2 times; Bus driver D4 and bus driver D5 output information code successively, when bus driver D4 output information code, bus driver D5 output is high level entirely, and bus driver D5 is output information code successively, and bus driver D4 output is high level entirely; 128 LED light are arranged in 8 LED light of every row, and one has 16 row, form the LED matrix of 16 × 8.
As Fig. 5, described telecommunication circuit comprises resistance R 1～R4, serial ports transceiver D2, connector X1, jumper wire device X5; Serial ports transceiver D2 is for the transmitting-receiving of serial data and the conversion of data level; Resistance R 1 is a pull-up resistor, serial ports transceiver D2 /RE in low level state, makes serial ports transceiver D2 be operated in accepting state while holding level with both hands; In the time that needs send data, serial ports transceiver D2 /RE end will transfer high level state to, and pull-up resistor R1 can provide pulling drive electric current, accelerates the switching of serial ports transceiver operating state; Resistance R 2 and resistance R 3 are two current-limiting resistances, for preventing that order wire short circuit from burning out serial ports transceiver; Resistance R 4, jumper wire device X5 are that a terminal build-out resistor is selected circuit, for signal transmssion line coupling, prevent signal reflex.
The workflow of time-sharing multiplex keyboard reading scan circuit of the present invention is: governor circuit is communicated by letter with host computer by telecommunication circuit, the key assignments of codan lamp state information, transmission button.Governor circuit timesharing rotation visit keyboard scanning circuit and reading scan circuit, the partial circuit in keyboard scanning circuit and reading scan circuit is multiplexing, in the access keyboard scanning circuit stage, it belongs to keyboard scanning circuit; In the access reading scan circuit stage, it belongs to reading scan circuit.
Keyboard matrix scanning process is: governor circuit first supervisory keyboard scanning circuit is operated in input state, be high level entirely by 8 horizontal scanning lines of reading scan circuit output keyboard matrix, governor circuit reads 8 column scan lines of keyboard matrix, be low level as complete, indicate to be pressed without button, if any high level, represent that a button is pressed.If any high level, only represent that a button is pressed, specifically which key is not also known, now needs to carry out next round scanning work.Governor circuit supervisory keyboard row matrix scan line only has a line output high level at every turn, and 8 horizontal scanning lines are exported in turn, high level of every output, and governor circuit just reads 8 column scan lines of primary key dish matrix, thereby judges the item of the button that is pressed.
LED matrix-scanning process is: governor circuit first supervisory keyboard scanning circuit is operated in output state, export LED matrix column scan line by keyboard scanning circuit, only has a row output high level at every turn, governor circuit is exported the information code (8) of this row correspondence by reading scan circuit, light corresponding LED light.Article 8, column scan line is exported in turn, circulates 2 times, thereby completes refreshing 128 LED light.
Although the present invention is illustrated hereinbefore according to preferred embodiment, this does not represent that scope of the present invention is confined to above-mentioned structure, as long as the structure being covered by this invention claim is all within protection range.Those skilled in the art are reading the equivalent substitution structure that can develop easily after above-mentioned explanation, and equalization variation and the modification under the spirit that does not depart from the present invention and scope, done, within all should being covered by protection range of the present invention.
Claims (5)
1. for the time-sharing multiplex keyboard reading scan circuit of fire alarm control unit, it is characterized in that, comprise governor circuit, keyboard scanning circuit, reading scan circuit and telecommunication circuit; Described keyboard scanning circuit, reading scan circuit and telecommunication circuit are all connected with described governor circuit;
Keyboard scanning circuit, for obtaining the keyboard signal of pressing and upspring, and sends the signal of acquisition to governor circuit;
Reading scan circuit, for obtaining the control signal of governor circuit, and according to the switch of this control signal control LED light;
Telecommunication circuit, for communicating by letter between governor circuit and host computer, receives the outside demonstration information that host computer sends, and the button value detecting is sent to host computer;
Governor circuit, the signal sending for receiving keyboard scanning circuit, reading scan circuit and telecommunication circuit, and the control signal of generation is sent to keyboard scanning circuit, reading scan circuit and telecommunication circuit.
2. time-sharing multiplex keyboard reading scan circuit according to claim 1, is characterized in that, described governor circuit comprises single-chip microcomputer D1, resistance R 5～R12, resistance R 18, capacitor C 7, capacitor C 8, capacitor C 10, crystal G1 and address wire jumper X3; Described capacitor C 7, capacitor C 8 and a clock oscillation circuit of crystal G1 composition, for single-chip microcomputer, D1 provides clock signal; Resistance R 18 and capacitor C 10 form an electrify restoration circuit, for single-chip microcomputer provides reset signal; Address wire jumper X3 is for configuring the mailing address of governor circuit; Resistance R 5～R12 forms a pull-up circuit, for strengthening the P0 mouth driving force of single-chip microcomputer D1; Single-chip microcomputer D1, by P0 mouth, P1 mouth supervisory keyboard scanning circuit, realizes the function of supervisory keyboard matrix; Single-chip microcomputer D1, by P0 mouth, P1 mouth, P2 mouth control reading scan circuit, realizes the function of management LED matrix; Wherein P0 mouth, P1 mouth are keyboard scanning circuit and the shared port of reading scan circuit.
3. time-sharing multiplex keyboard reading scan circuit according to claim 1, it is characterized in that, described keyboard scanning circuit comprises resistance R 16～R23, resistance R 43～R50, diode V128～V135, bus driver D3, bus driver D4 and keyboard matrix S0～S63; Resistance R 16～R23 is pull down resistor, for determining that what single-chip microcomputer D1 read by P0 mouth is all low level not when being pressed; Resistance R 16～R23 also forms a bleeder circuit with resistance R 43～R50, and its voltage ratio guarantees that, in the time having key to be pressed, what single-chip microcomputer D1 read is high level; Diode V128～V135 forms an anti-button short circuit current, in the time that two keys of same row are pressed simultaneously, prevents the horizontal scanning line short circuit that it is corresponding; Bus driver D3 time-sharing work is under two states: input and output, and the switching of its working method is controlled by single-chip microcomputer D1; In the keyboard scan period, bus driver D3 works in input state, and single-chip microcomputer D1 is by the line scan signals of bus driver D4 output key, and by bus driver, D3 reads key-press status; 64 button S0～S63 are arranged in 8 buttons of every row, and one has 8 row, form the keyboard matrix of 8 × 8.
4. time-sharing multiplex keyboard reading scan circuit according to claim 1, is characterized in that, described reading scan circuit comprises resistance R 27～R42, bus driver D3, bus driver D4, bus driver D5 and LED matrix; Resistance R 27～R42 is 16 current-limiting resistances, and the electric current while lighting for limiting LED prevents that bus driver is because of the excessive damage of electric current; Bus driver D3 works in output state in the reading scan period, and B0～B7 pin of bus driver D3 is exported high level successively, circulates 2 times; Bus driver D4 and bus driver D5 output information code successively, when bus driver D4 output information code, bus driver D5 output is high level entirely, and bus driver D5 is output information code successively, and bus driver D4 output is high level entirely; 128 LED light are arranged in 8 LED light of every row, and one has 16 row, form the LED matrix of 16 × 8.
5. time-sharing multiplex keyboard reading scan circuit according to claim 1, is characterized in that, described telecommunication circuit comprises resistance R 1～R4, serial ports transceiver D2, connector X1, jumper wire device X5; Serial ports transceiver D2 is for the transmitting-receiving of serial data and the conversion of data level; Resistance R 1 is a pull-up resistor, serial ports transceiver D2 /RE in low level state, makes serial ports transceiver D2 be operated in accepting state while holding level with both hands; In the time that needs send data, serial ports transceiver D2 /RE end will transfer high level state to, and pull-up resistor R1 can provide pulling drive electric current, accelerates the switching of serial ports transceiver operating state; Resistance R 2 and resistance R 3 are two current-limiting resistances, for preventing that order wire short circuit from burning out serial ports transceiver; Resistance R 4, jumper wire device X5 are that a terminal build-out resistor is selected circuit, for signal transmssion line coupling, prevent signal reflex.
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| CN201110421160.XA CN102523003B (en) | 2011-12-15 | 2011-12-15 | Time-sharing multiplexing keyboard display scanning circuit applied to fire alarm controller |
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| CN201110421160.XA CN102523003B (en) | 2011-12-15 | 2011-12-15 | Time-sharing multiplexing keyboard display scanning circuit applied to fire alarm controller |
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| CN102523003B true CN102523003B (en) | 2014-06-18 |
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Families Citing this family (2)
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| CN105024680A (en) * | 2015-07-20 | 2015-11-04 | 广东格兰仕集团有限公司 | Data sending and button detection multiplexing circuit and processing method of program thereof |
| CN106683604B (en) * | 2017-03-22 | 2020-07-21 | 广东携创电机有限公司 | Multiplexing processing circuit for L ED display and key detection |
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| JPH1185368A (en) * | 1997-09-05 | 1999-03-30 | Sharp Corp | One-chip microcomputer system |
| JP3058430B2 (en) * | 1990-05-28 | 2000-07-04 | 株式会社東芝 | Key scan device |
| CN101924563A (en) * | 2009-06-16 | 2010-12-22 | 厦门敏讯信息技术股份有限公司 | Keyboard scanning method |
| CN102142846A (en) * | 2010-01-28 | 2011-08-03 | 环旭电子股份有限公司 | Keyboard scanning device as well as key matrix circuit and scanning method thereof |
| CN202424693U (en) * | 2011-12-15 | 2012-09-05 | 蚌埠依爱消防电子有限责任公司 | Display scanning circuit of time sharing multiplex keyboard for fire alarm controller |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0645725B2 (en) * | 1988-01-19 | 1994-06-15 | 矢崎総業株式会社 | Graphite fiber-containing composite resin composition |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3058430B2 (en) * | 1990-05-28 | 2000-07-04 | 株式会社東芝 | Key scan device |
| JPH1185368A (en) * | 1997-09-05 | 1999-03-30 | Sharp Corp | One-chip microcomputer system |
| CN101924563A (en) * | 2009-06-16 | 2010-12-22 | 厦门敏讯信息技术股份有限公司 | Keyboard scanning method |
| CN102142846A (en) * | 2010-01-28 | 2011-08-03 | 环旭电子股份有限公司 | Keyboard scanning device as well as key matrix circuit and scanning method thereof |
| CN202424693U (en) * | 2011-12-15 | 2012-09-05 | 蚌埠依爱消防电子有限责任公司 | Display scanning circuit of time sharing multiplex keyboard for fire alarm controller |
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