Specific implementation mode
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation describes, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
An embodiment of the present invention provides a kind of circuits of multiplexed port, as shown in Figure 1, including:Multiplex interface 11, for connecting
Connect external plug.
Wherein, multiplex interface 11 includes the first pin 111, second pin 112, third pin 113 and the 4th pin 114.
4th pin 114 is grounded, and third pin 113 is connect with first power source unit 12.First pin 111 of multiplex interface 11, second
Pin 112 is connect with detection process unit 13, and third pin 113 is connect with detection process unit 13 and converting unit 14, external
Plug includes serial interface plug or infrared IR extended lines plug.
Converting unit 14 is connect with detection process unit 13, for what is transmitted according to the third pin 113 of multiplex interface 11
Level signal carries out signal conversion, and the signal of conversion is sent to detection process unit 13.
Detection process unit 13 is connect with control processor, for what is transmitted according to the third pin 113 of multiplex interface 11
Level signal determines the type for the external plug for being inserted into multiplex interface 11, and the letter for the conversion transmitted according to converting unit 14
Number, the transmission of signal is carried out between the first pin 111 and second pin 112 of multiplex interface 11, control processor.
It should be noted that in the present invention being improved to the circuit of existing IR extended lines, it is made to realize IR
While the function of the port of (Infrared Radiation, infrared) extended line, the function of serial ports can also be realized.Due to IR
Extended line plug includes power connector end, IR signal connection ends and ground terminal, and serial interface plug includes rs 232 serial interface signal receiving terminal, serial ports
Signal sending end, serial ports power connector end and ground terminal.And the IR signal connection ends of IR extended line plugs and serial interface plug
Rs 232 serial interface signal receiving end signal is the circuit for sending the signal to multiplexed port;The rs 232 serial interface signal transmitting terminal and IR of serial interface plug
The power connector end of extended line plug is the circuit output signal of multiplexed port, therefore for the ease of multiplexing, by serial interface plug
Rs 232 serial interface signal receiving terminal and IR extended line plugs IR signal connection end common ports multiplexing circuit multiplex interface it is same
One pin, the circuit of the power connector end common port multiplexing of the rs 232 serial interface signal transmitting terminal and IR extended line plugs of serial interface plug
The same pin of multiplex interface.
Specifically, including multiplex interface 11, first power source unit 12, detection process unit 13 in the circuit of multiplexed port
And converting unit 14.Wherein, multiplex interface 11 includes the first pin 111, second pin 112, third pin 113 and the 4th
Pin 114.Multiplex interface 11 is connect with external plug, and as, serial interface plug or IR extended line plugs can be inserted by user
To multiplex interface 11, it is connect with each pin of multiplex interface 11.4th pin 114 of multiplex interface 11 is grounded, therefore, serial ports
The ground terminal and the ground terminal in IR extended line plugs of plug are connect with the 4th pin 114 of multiplex interface 11.IR extended lines are inserted
The power connector end and serial interface plug rs 232 serial interface signal transmitting terminal of head are connect with the first pin 111 of multiplex interface 11.Serial interface plug
Rs 232 serial interface signal receiving terminal and the IR signal connection ends of IR extended line plugs and the second pin 112 of multiplex interface 11 connect.IR
Ground terminal in extended line plug is connect with the third pin 113 of multiplex interface 11, and the serial ports power connector end of serial interface plug
It is connect with the third pin 113 of multiplex interface 11.It follows that the multiplexing for being inserted into the electric current of multiplexed port in serial interface plug connects
Mouth 11, when being inserted into the multiplex interface 11 of circuit of multiplexed port with IR extended line plugs, the multiplexing of the circuit of multiplexed port connects
The level signal of the third pin 113 of mouth 11 is different.Therefore, third pin 113 is connect with first power source unit 12, third
Pin 113 is connect with detection process unit 13 and converting unit 14.So, it is inserted into multiplexed port in IR extended line plugs
Electric current multiplex interface 11 when, since the ground terminal of IR extended line plugs is connect with third pin 113, the first power supply
The voltage that unit 12 provides is connect by third pin 113 with the ground terminal of IR extended line plugs, as first power source unit 12
Ground connection, at this point, the level letter that the detection process unit 13 of the circuit of multiplexed port is obtained from the third pin 113 of multiplex interface 11
Number be low level signal, at this point, detection process unit 13 can determine be inserted into the external plug of multiplex interface 11 be IR extension
Line plug.
When serial interface plug is inserted into the multiplex interface 11 of electric current of multiplexed port, since the serial ports power supply of serial interface plug connects
It connects end to connect with third pin 113, therefore, the voltage that first power source unit 12 provides passes through third pin 113 and serial interface plug
Serial ports power connector end connection, as first power source unit 12 be serial interface plug power supply.At this point, the inspection of the circuit of multiplexed port
It is high level signal to survey the level signal that processing unit 13 is obtained from the third pin 113 of multiplex interface 11, at this point, detection process
Unit 13 can determine that the external plug for being inserted into multiplex interface 11 is serial interface plug.
After rotating unit 14 gets level signal by third pin, this level signal can be converted, as
The high level signal of reception is converted into low level signal, the low level signal of reception is converted into high level signal.It will conversion
Signal afterwards is sent to the detection process unit 13 of its connection.
Detection process unit 13 can be determined external according to the level signal that the third pin 113 of multiplex interface 11 transmits
The type of plug.As, detection process unit 13 is in the level signal for the transmission of third pin 113 for receiving multiplex interface 11
When high level signal, it may be determined that external plug is serial interface plug;It is transmitted in the third pin 113 for receiving multiplex interface 11
When level signal is low level signal, it may be determined that external plug is IR extended line plugs.Determining the external of multiplex interface
After the type of plug, the signal for the conversion that can be transmitted according to converting unit 14, in 11 first pin 111 and second of multiplex interface
Pin 112 carries out the transmission of signal between control processor.
When external plug is IR extended line plugs, detection process unit 13 can be to the first pin of multiplex interface 11
111 provide voltage signal, to give IR extended line plugs to power.IR is received by the second pin 112 of multiplex interface 11 to extend
The IR signals that line plug is sent, and by this IR signal transmission to control processor.In this way, control processor can be according to reception
IR signals are handled accordingly.
When external plug is serial interface plug, detection process unit 13 can be carried to the first pin 111 of multiplex interface 11
For serial ports output signal, at this point, when needing to send serial ports output signal to serial interface plug, control processor can be at detection
It manages unit 13 and sends serial ports output signal, serial ports output signal can be sent to multiplex interface 11 by detection process unit 13 at this time
The first pin 111, and the rs 232 serial interface signal transmitting terminal that serial interface plug can be connect by the first pin 111 with multiplex interface 11
The serial ports output signal for getting control processor transmission, to which serial interface plug can carry out accordingly according to serial ports output signal
Processing.It, can be to the first pin 111 of multiplex interface 11 when serial interface plug need to send serial ports input signal to control processor
Serial ports input signal is sent, detection process unit 13, detection process unit are sent to by the first pin 111 of multiplex interface 11
This serial ports input signal can be sent to control processor by 13, so that control processor carries out accordingly according to serial ports input signal
Signal processing.
Further, when external plug is serial interface plug, detection process unit 13 can be converted according to converting unit 14
Signal, associated components when with external plug being IR extended line plugs in it are closed.It is IR extended lines in external plug
When plug, the signal that detection process unit 13 can be converted according to converting unit 14 will be inserted with external plug for serial ports in it
Associated components when head are closed.
Multiplex interface in the circuit of multiplexed port through the invention can be connect with external plug.This external plug
Can be that serial interface plug can also be infrared IR extended lines plug.That is, the circuit of multiplexed port in the present invention be by
Realize that the circuit multiplexer of serial ports extends the circuit of line jack to realization IR.So, the circuit of the multiplexed port in the present invention
The difference of level signal transmitted according to the third pin of multiplex interface of detection process unit, carry out different signal transmissions,
So as to convenience, the inexpensive purpose for realizing serial ports terminal in DTV STB.
Further, the circuit of above-mentioned multiplexed port, as shown in Fig. 2, further including:Control switch 15, second power source unit
16.Detection process unit 13 includes:First triple gate 131, the second triple gate 132, third triple gate 133 and the 4th triple gate
134。
At this point, the first pin 111 of multiplex interface 11, second pin 112 are connect with detection process unit 13, third pin
113 connect with detection process unit 13, converting unit 14 connect with detection process unit 13 including:
Control processor is connect with the first end of the first triple gate 131, the control of converting unit 14 and the first triple gate 131
End connection, the second end of the first triple gate 131 are connect with the first pin 111 of multiplex interface 11.
The second pin 112 of multiplex interface 11 is connect with the first end of the second triple gate 132, converting unit 14 and the two or three
The control terminal of state door 132 connects, and the second end of the second triple gate 132 is connect with control processor.
The second pin of multiplex interface 11 is connect with the first end of third triple gate 133, the third pin of multiplex interface 11
113 connect with the control terminal of third triple gate 133, and the second end of third triple gate 133 is connect with control processor.
The first end of 4th triple gate 134 is grounded, the control of the third pin 113 and the 4th triple gate 134 of multiplex interface 11
The second end of end connection processed, the 4th triple gate 134 is connect with the control terminal of control switch 15, and second power source unit 16 is opened with control
15 control terminal connection is closed, the first end of control switch 15 is connect with second power source unit 16;Control switch 15 second end and
First pin 111 of multiplex interface 11 connects.
Specifically, the triple gate in the embodiment of the present invention is control terminal when receiving low level signal, first end is controlled
And second end conducting, when receiving high level signal, controls first end and second end disconnects.In this way, in user by serial interface plug
When being inserted into the multiplex interface 11 of circuit of multiplexed port, at this point, the rs 232 serial interface signal receiving terminal of serial interface plug and multiplex interface 11
Second pin 112 connect, the rs 232 serial interface signal transmitting terminal of serial interface plug connect with the first pin 111 of multiplex interface 11, serial ports
The serial ports power connector end of plug is connect with the third pin 113 of multiplex interface 11, the ground terminal and multiplex interface of serial interface plug
11 the 4th pin connection 114.At this point, since third pin 113 is connect with first power source unit 12, the first power supply list
Member 12 can be powered by third pin 113 to serial interface plug.Also, third pin 113 is connect with converting unit 14, by
It can be powered for serial interface plug by third pin 113 in first power source unit 12, therefore, converting unit 14 can pass through third
Pin 113 gets high level signal, and high level signal can be converted to low level signal by converting unit 14.
The control terminal of the first triple gate 131 in detection process unit 13 is connect with converting unit 14, due to converting unit
14 outputs are low level signal, therefore first end and second end is connected in the first triple gate 131.And the of the first triple gate 131
One end is connect with control processor, and the second end of the first triple gate 131 is connect with the first pin 111 of multiplex interface 11, therefore,
Serial ports output signal can be sent to the first pin 111 of multiplex interface 11 by control processor by the first triple gate 131, i.e.,
For serial ports output signal can be sent to first by control processor when needing to send serial ports output signal to serial interface plug
The first end of triple gate 131, since the first end of the first triple gate 131 is connected with second end, the first triple gate 131 can
Serial ports output signal is transmitted to second end, serial ports output signal is transmitted to multiplexing and connect by the second end of the first triple gate 131
First pin 111 of mouth 11.And then serial ports output signal is sent to by serial interface plug by the first pin 111 of multiplex interface 11
Rs 232 serial interface signal transmitting terminal.
The control terminal of second triple gate 132 is connect with rotating unit 14, since the output of converting unit 14 is low level letter
Number, therefore the second triple gate 132 conducting first end and second end.And the first end connection multiplexing interface 11 of the second triple gate 132
Second pin 112, the second end of the second triple gate 132 connects control processor, and therefore, serial interface plug can input serial ports
Signal is sent to the second pin 112 of multiplex interface 11 by rs 232 serial interface signal receiving terminal.The second pin 112 of multiplex interface 11 can
Serial ports input signal to be transmitted to the first end of the second triple gate 132, due to the first end and second end of the second triple gate 132
Conducting, therefore serial ports input signal can be transmitted to second end by the second triple gate 132, the second end of the second triple gate 132 with
Control processor connects, therefore serial ports input signal can be transmitted to control processor by the second triple gate 132.
The control terminal of third triple gate 133 is connect with the third pin 113 of multiplex interface 11, due to first power source unit 12
Can be that serial interface plug is powered by third pin 113, therefore, the control terminal of third triple gate 133 from multiplex interface 11 the
Three pins 113 get high level signal.Third triple gate 133 disconnects first end and second end.Due to the of multiplex interface 11
Two pins 112 are connect with the first end of third triple gate 133, and control processor is connect with the second end of third triple gate 133, because
This, the second pin 112 of multiplex interface 11 can not be communicated by third triple gate 133 with control processor.
The control terminal of 4th triple gate 134 is connect with the third pin 113 of multiplex interface 11, due to first power source unit 12
Can be that serial interface plug is powered by third pin 113, therefore, the control terminal of the 4th triple gate 134 from multiplex interface 11 the
Three pins 113 get high level signal.4th triple gate 134 disconnects first end and second end.And the of the 4th triple gate 134
One end is grounded, and second end is connect with the control of control switch 15.And control switch 15 control terminal also with second power source unit 16
Connection, therefore, the control terminal of control switch 15 receive the high level signal of the offer of second power source unit 16.Since control switchs
15 switches be connected for low level signal, therefore in control switch 15 its first end is not turned on when receiving high level signal
And second end.So that second power source unit 16 is not powered to the first pin 111 of multiplex interface 11.
So, by the open and close of each triple gate of above-mentioned detection process unit 13, serial interface plug is realized
Communication between control processor.To make the circuit of multiplexed port realize the function of serial ports terminal.
When IR extended line plugs are inserted into the multiplex interface 11 of circuit of multiplexed port by user, at this point, IR extended lines
The power connector end of plug is connect with the first pin 111 of multiplex interface 11, IR signal connection ends and the second of multiplex interface 11
Pin 112 connects, and ground terminal is connect with the third pin 113 of multiplex interface 11 and the 4th pin 114.At this point, since third is drawn
Foot 113 is connect with first power source unit 12, and therefore, first power source unit 12 is grounded by third pin 113.Third pin 113
It is connect with converting unit 14, since first power source unit 12 and third pin 113 are grounded, converting unit 14 can pass through
Third pin 113 gets low level signal, and low level signal can be converted to high level signal by converting unit 14.
The control terminal of the first triple gate 131 in detection process unit 13 is connect with converting unit 14, due to converting unit
14 outputs are high level signal, and therefore, the first triple gate 131 disconnects first end and second end.And the of the first triple gate 131
One end is connect with control processor, and the second end of the first triple gate 131 is connect with the first pin 111 of multiplex interface 11, at this point,
Control processor can not be communicated by the first triple gate 131 with the first pin 111 of multiplex interface 11.
Similarly, the control terminal of the second triple gate 132 is connect with rotating unit 14, since the output of converting unit 14 is high electricity
Ordinary mail number, at this point, the second triple gate 132 disconnects first end and second end.And the first end connection multiplexing of the second triple gate 132 connects
The second end of the second pin 112 of mouth 11, the second triple gate 132 connects control processor, and therefore, control processor can not pass through
Second triple gate 132 is communicated with the second pin 112 of multiplex interface 11.
The control terminal of third triple gate 133 is connect with the third pin 113 of multiplex interface 11, since third pin 113 connects
Ground, therefore the control terminal of third triple gate 133 gets low level signal from third pin 113, at this point, third triple gate 133
Its first end can be connected with second end.And the second pin 112 of multiplex interface 11 and the first end of third triple gate 133 connect
It connects, control processor is connect with the second end of third triple gate 133, and therefore, IR extended line plugs are needed IR signal transmissions extremely
When control processor, IR signals can be transmitted to the multiplex interface 11 of IR signal connection ends connection by IR signal connection ends
Second pin 112.The second pin 112 of multiplex interface 11 can be by IR signal transmissions to the first end of third triple gate 133.By
It is connected with second end in the first end of third triple gate 133, therefore third triple gate 133 can be by IR signal transmissions to second
IR signals are transmitted to control processor by end, third triple gate 133 by its second end.
The control terminal of 4th triple gate 134 is connect with the third pin 113 of multiplex interface 11, since third pin 113 connects
Ground, therefore the control terminal of the 4th triple gate 134 gets low level signal from third pin 113, at this point, the 4th triple gate 134
Its first end can be connected with second end.And the first end ground connection of the 4th triple gate 134, the control of second end and control switch 15
System connection, at this point, when its first end is connected the 4th triple gate 134 with second end, then the second end of the 4th triple gate 134
Ground connection, at this point, the control terminal ground connection of control switch 15, the control terminal to control switch 15 can get low level signal,
Its first end and second end can be connected at this time.The first end for controlling switch 15 connects second power source unit 16, second end connection
First pin 111 of multiplex interface 11, so, second power source unit 16 can be the first pin 111 of multiplex interface 11
Power supply, since the first pin 111 of multiplex interface 11 is connect with the power connector end of IR extended line plugs, second source list
Member 16 can be that the power connector end of IR extended line plugs is powered.
So, by the open and close of each triple gate of above-mentioned detection process unit 13, IR extended lines are realized
Communication between plug and control processor, from while the circuit of multiplexed port can be made to realize the function of serial ports terminal,
It can guarantee that the normal realization of the function of IR extended lines port as completes serial port circuit being multiplexed to IR and prolong in the present invention
Long line circuit.
Further, the circuit of above-mentioned multiplexed port, as shown in figure 3, further including:First stablizes unit 17, and second stablizes
Unit 18 and third stablize unit 19.
Wherein, the first steady dot element 17 is connect with the second end of the first triple gate 131;Second stablizes unit 18 and the two or three
The second end of state door 132 connects;Third is stablized unit 19 and is connect with the second end of third triple gate 133.First stablizes unit 17,
For providing burning voltage for the first triple gate 131.Second stablizes unit 18, stablizes electricity for being provided for the second triple gate 132
Pressure.Third stablizes unit 19, for providing burning voltage for third triple gate 133.
So, stablize unit 17 by first, it can be first that the second stabilization unit 18 and third, which stablize unit 19,
Triple gate 131, the second triple gate 132, third triple gate 133 are more stablized.
Further, refering to what is shown in Fig. 3, the first steady dot element 17 includes:First power module 171 and the first power module
The first resistor 172 of 171 connections.
At this point, the first steady dot element 17 connect with the second end of the first triple gate 131 including:First resistor 172 it is another
End is connect with the second end of the first triple gate 131.
Second steady dot element 18 includes:The second resistance 182 that second power supply module 181 is connect with second power supply module 181.
At this point, second stabilization unit 18 connect with the second end of the second triple gate 132 including:Second resistance 182 it is another
End is connect with the second end of the second triple gate 132.
The steady dot element of third 19 includes:The 3rd resistor 192 that third power module 191 is connect with third power module 191.
At this point, third stablize unit 19 connect with the second end of third triple gate 133 including:3rd resistor 192 it is another
End is connect with the second end of third triple gate 133.
Further, above-mentioned first resistor 172 is 10k ohm.Second resistance 182 is 10k ohm.3rd resistor 192 is
10k ohm.
Further, as shown in figure 4, converting unit 14 includes:Switch module 141, the 4th power module 142 and output end
143.Wherein, the 4th power module 142 and output end 143 are connect with the first end of switch module 141, and the of switch module 142
Two ends are grounded.
At this point, third pin 133 connect with converting unit 14 including:The control terminal of third pin 133 and switch module 141
Connection.
Converting unit 14 connect with detection process unit 13 including:The output end 143 of converting unit 14 and detection process list
Member 13 connects.
Specifically, the third pin 113 of multiplex interface 11 is connect with the control terminal of switch module 141, in this way, switch module
141 level signals exported according to the level signal control output end of the third pin 113 of multiplex interface 11 transmission.It is connect in multiplexing
When the third pin 113 of mouth 11 is high level signal, this high level signal is transmitted to the control terminal of switch module 141, is switched
After the control terminal of module 141 receives high level signal, control 141 first end of switch module is connected with second end, at this point, due to
The second end of switch module 141 is grounded, and therefore, the first end of switch module 141 also corresponds to be grounded, at this time with switch module
The 4th power module 142 and output end 143 of 141 first end connection are equivalent to ground connection, and output end 143 exports low level letter
Number.The output end 143 of converting unit 14 is connect with detection process unit 13, at this point, the output end 143 of converting unit 14 can incite somebody to action
Low level signal is output to detection process unit 13.So, the control terminal of the switch module 141 of converting unit 14 receives
The high level signal that the third pin 113 of multiplex interface 11 transmits, and exported to the letter of detection process unit 13 in output end 143
Number be low level signal, realize the conversion of signal.
When the third pin 113 of multiplex interface 11 is low level signal, this low level signal is transmitted to switch module
141 control terminal, after the control terminal of switch module 141 receives low level signal, control 141 first end of switch module and second
End disconnects, at this point, the 4th power module 142 and output end 143 connect, therefore, the 4th power module 142 is that output end 143 carries
For high level signal, so as in 143 high level signal of output end.Therefore, the output end 143 of converting unit 14 can will be high
Level signal is output to detection process unit 13.So, the control terminal of the switch module 141 of converting unit 14 receives multiple
The low level signal transmitted with the third pin 113 of interface 11, and exported to the signal of detection process unit 13 in output end 143
For high level signal, the conversion of signal is realized.
Further, above-mentioned switch module 141 is NPN type triode.4th power module 142 is 3.3v power modules.
Further, the circuit of above-mentioned multiplexed port, as shown in figure 5, further including:4th resistance 20, the 5th resistance 21, the
Six resistance 22, the 7th resistance 23, capacitance 24.Above-mentioned control switch 15 is PNP type triode.
Wherein, the second end of the 4th triple gate 134 with control switch 15 control terminal connect including:4th triple gate 134
Second end by the 4th resistance 20 with control switch 15 control terminal connect.
Control switch 15 second end connect with the first pin 111 of multiplex interface 11 including:
The second end of control switch 15 is connect by the 6th resistance 22 with the first pin 111 of multiplex interface 11.
One end of 5th resistance 21 connects second power source unit 16, and the other end is connect with the control terminal of control switch 15.The
The second end of one end of seven resistance 23 and control switch 15, other end ground connection;One end of capacitance 24 is grounded, and the other end connects with multiplexing
The first pin 111 connection of mouth 11.
In this way, the 4th resistance 20, the 5th resistance 21 can have metering function, and certain protection is played to control switch 15
Effect.Similarly, the 6th resistance 22, the 7th resistance 23 and capacitance 24 can have the first pin 111 of multiplex interface 11 certain
Protective effect.
Further, detection process unit 13 includes:74HCU125 chips.
Further, refering to what is shown in Fig. 6, further including in converting unit 14:8th resistance and the 9th resistance.Wherein,
Three pins 113 connect with the control terminal of switch module 141 including:Third pin 113 is connect with one end of the 8th resistance, the 8th electricity
The other end of resistance is connect with the control terminal of switch module 141.As, third pin 113 passes through the 8th resistance and switch module 141
Control terminal connection.
4th power module 142 connect with the first end of switch module 141 including:4th power module 142 and the 9th electricity
One end of resistance connects, and the other end of the 9th resistance is connect with the first end of switch module 141.As, the 4th power module 142 is logical
The 9th resistance is crossed to connect with the first end of switch module 141.
Illustratively, as shown in Figure 6, it is assumed that detection process unit 13 is 74HCU125 chips.Switch module 141 is NPN
Type triode, first power source unit 12, second power source unit 16 are 3.3v power supplys, and control switch 15 is PNP type triode, the
One power module 171, second power supply module 181, third power module 191 are 3.3v power supplys, and first resistor 172 is resistance
R1, second resistance 182 are resistance R2, and 3rd resistor 192 is resistance R3, and the 4th resistance 20 is resistance R4, and the 5th resistance 21 is electricity
R5 is hindered, the 6th resistance 22 is resistance R6, and the 7th resistance 23 is resistance R7, and capacitance 24 is capacitance CS1.Switch module 141 is NPN type
Triode, the 4th power module are 3.3v power supplys, and the 8th resistance is resistance R8, and the 9th resistance is resistance R9.
Comprising there are four triple gates in 74HCU125 chips, wherein the pin 1 of 74HCU125 chips is the first triple gate
Control terminal, pin 2 be the first triple gate first end, pin 3 be the first triple gate second end, pin 4 be the second tri-state
The control terminal of door, pin 5 are the first end of the second triple gate, and pin 6 is the second end of the second triple gate, and pin 10 is third
The control terminal of triple gate, pin 9 are the first end of third triple gate, and pin 8 is the second end of third triple gate, and pin 13 is the
The control terminal of 4th triple gate, pin 12 are the first end of the 4th triple gate, and pin 11 is the second end of the 4th triple gate, pin
14 connection power supplys, are 74HCU125 chip power supplies, and pin 7 is grounded.Multiplex interface 11 includes that there are four pins, and respectively first draws
Foot 111, second pin 112, third pin 113 and the 4th pin 114.4th pin 114 is grounded.Assuming that the electricity of multiplexed port
Include resistance R10 in road, 3.3v power supplys are connect by resistance R10 with third pin 113 at this time.Third pin 113 with
The pin 10 and pin 13 of 74HCU125 chips connect, and third pin 113 passes through the control terminal of resistance R8 and NPN type triode
Connection.The first end of NPN type triode is connect with one end of output end 143 and resistance R9, the other end and the 3.3v electricity of resistance R9
Source connects.Output end 143 is connect with the pin 1 of 74HCU125 chips and pin 4.At the pin 2 of 74HCU125 chips and control
Device connection is managed, the pin 3 of 74HCU125 chips is connect with the first pin 111 and resistance R1 of multiplex interface 11 respectively, resistance R1
The other end connect with 3.3v power supplys;The pin 5 of 74HCU125 chips is connect with the second pin 112 of multiplex interface 11,
The pin 6 of 74HCU125 chips is connect with control processor and resistance R2 respectively, and the other end of resistance R2 is connect with 3.3v power supplys;
The pin 7 of 74HCU125 chips is grounded, and the pin 9 of 74HCU125 chips is connect with the second pin 112 of multiplex interface 11,
The pin 8 of 74HCU125 chips is connect with control processor and resistance R3 respectively, and the other end of resistance R3 is connect with 3.3v power supplys;
The pin 12 of 74HCU125 chips is grounded, and the pin 11 of 74HCU125 chips is connect with resistance R4, the other end difference of resistance R4
The control terminal of connection resistance R5 and PNP type triode, the other end connection 3.3v power supplys of resistance R5, the first of PNP type triode
End is connect with 3.3v power supplys, and the second end of PNP type triode is separately connected resistance R6 and resistance R7, the other end connection of resistance R6
First pin 111 of multiplex interface 11, the other end ground connection of resistance R7, one end of capacitance CS1 is connected to the other end of resistance R6
Between the first pin 111 of multiplex interface 11, other end ground connection.The pin 14 of 74HCU125 chips connects 3.3v power supplys, with
Just working power is provided for 74HCU125 chips.
So, when serial interface plug is inserted into the multiplex interface 11 of circuit of multiplexed port by user, at this point, serial ports
The rs 232 serial interface signal receiving terminal of plug is connect with the second pin 112 of multiplex interface 11, the rs 232 serial interface signal transmitting terminal of serial interface plug with
First pin 111 of multiplex interface 11 connects, the serial ports power connector end of serial interface plug and the third pin 113 of multiplex interface 11
Connection, the ground terminal of serial interface plug connect 114 with the 4th pin of multiplex interface 11.Due to third pin 113 and 3.3v power supplys
Connection, 3.3v power supplys can be serial interface plug serial ports power connector end power, and third pin 113 by resistance R8 with
The control terminal of NPN type triode connects, at this point, the control terminal of NPN type triode can get high electricity from third pin 113
Ordinary mail number.After the control terminal of NPN type triode gets high level signal, its first end and second end is connected, due to second end
Ground connection, the 3.3v power grounds of first end connection, the low level signal of the output of output end 143 at this time.
The pin 1 of 74HCU125 chips is connect with output end 143, and pin 1 is the first triple gate of 74HCU125 chips
The control terminal of control terminal, the first triple gate receives low level signal, therefore the first triple gate is connected, first end and second is connected
End.And the pin 2 that the first end of the first triple gate is 74HCU125 chips, the second end of the first triple gate is 74HCU125 chips
Pin 3, therefore, the control processor being connect with the pin 2 of 74HCU125 chips can need to serial interface plug send go here and there
When mouth output signal, serial ports output signal is sent to the pin 2 of 74HCU125 chips, due to the pin 2 of 74HCU125 chips
And pin 3 is connected, therefore, serial ports output signal can be transmitted to pin 3, the pin of 74HCU125 chips by 74HCU125 chips
3 are transmitted to serial ports output signal the first pin 111 of multiplex interface 11.And then the first pin 111 for passing through multiplex interface 11
Serial ports output signal is sent to the rs 232 serial interface signal transmitting terminal of serial interface plug.
The control terminal of second triple gate of 74HCU125 chips is the pin 4 in 74HCU125 chips, is connected with output end 143
It connects, since the output of output end 143 is low level signal, the second triple gate conducting first end of 74HCU125 chips and the
Two ends.Pin 5 in 74HCU125 chips is the first end of the second triple gate, and the pin 6 in 74HCU125 chips is second
The second end of triple gate, in this way, when serial interface plug needs serial ports input signal being sent to control processor, it can be by serial ports
Input signal is sent to the second pin 112 of multiplex interface 11 by rs 232 serial interface signal receiving terminal.The second pin of multiplex interface 11
112 can be transmitted to serial ports input signal the pin 5 in 74HCU125 chips connected to it, due in 74HCU125 chips
Pin 5 and pin 6 be connected, therefore serial ports input signal can be transmitted to pin 6,74HCU125 chips by 74HCU125 chips
Interior pin 6 is connect with control processor, therefore serial ports input signal can be transmitted to control processor by 74HCU125 chips.
The control terminal of the third triple gate of 74HCU125 chips is the pin 10 of 74HCU125 chips, with multiplex interface 11
Third pin 113 connects, since 3.3v power supplys can be that serial interface plug is powered by third pin 113,74HCU125 cores
The pin 10 of piece gets high level signal from the third pin 113 of multiplex interface 11.Third triple gate disconnects first end and the
Two ends, due to the pin 9 that the first end of third triple gate is 74HCU125 chips, the second end of third triple gate is 74HCU125
The pin 8 of chip, therefore the pin 9 of 74HCU125 chips and pin 8 disconnect.Due to multiplex interface 11 second pin 112 with
The pin 9 of 74HCU125 chips connects, and control processor is connect with the pin 8 of 74HCU125 chips, therefore, multiplex interface 11
Second pin 112 can not be communicated by 74HCU125 chips with control processor.
The control terminal of 4th triple gate of 74HCU125 chips is the pin 13 of 74HCU125 chips, with multiplex interface 11
Third pin 113 connects, since 3.3v power supplys can be that serial interface plug is powered by third pin 113,74HCU125 cores
The pin 13 of piece gets high level signal from the third pin 113 of multiplex interface 11.4th triple gate disconnects first end and the
Two ends.Due to the pin 12 that the first end of the 4th triple gate is 74HCU125 chips, the second end of the 4th triple gate is
The pin 11 of 74HCU125 chips, therefore the pin 12 of 74HCU125 chips and pin 11 disconnect.And 74HCU125 chips draw
Foot 12 is grounded, and pin 11 is connected by the control terminal of resistance R4 and PNP type triode.And the control terminal of PNP type triode passes through
Resistance R5 is also connect with 3.3v power supplys, and therefore, the control terminal of PNP type triode receives the high level letter of 3.3v power supplys offer
Number.Due to the switch that PNP type triode is low level signal conducting, height is being received in the control terminal of PNP type triode
When level signal, it is not turned on its first end and second end.So that 3.3v power supplys are not to the first pin 111 of multiplex interface 11
Power supply.
In this way by the open and close of each triple gate of above-mentioned 74HCU125 chips, realize at serial interface plug and control
Manage the communication between device.To make the circuit of multiplexed port realize the function of serial ports terminal.
When IR extended line plugs are inserted into the multiplex interface 11 of circuit of multiplexed port by user, at this point, IR extended lines
The power connector end of plug is connect with the first pin 111 of multiplex interface 11, IR signal connection ends and the second of multiplex interface 11
Pin 112 connects, and ground terminal is connect with the third pin 113 of multiplex interface 11 and the 4th pin 114.Due to third pin 113
It is connect with 3.3v power supplys, therefore, 3.3v power supplys are grounded by third pin 113.Third pin 113 and pass through resistance R8 and NPN
The control terminal of type triode connects, since 3.3v power supplys and third pin 113 are grounded, the control terminal of NPN type triode can
To get low level signal by third pin 113, the control terminal due to NPN type triode is receiving high level signal
When, its first end and second end is just connected, therefore, the control terminal of NPN type triode can not be led when receiving low level signal
Lead to its first end and second end.At this point, 3.3v power supplys are connected by the first end and output end 143 of resistance R9 and NPN type triode
It connects.Since the first end and second end of NPN type triode disconnect, 3.3v power supplys are that output end 143 provides high level letter
Number.
The pin 1 of 74HCU125 chips is connect with output end 143, and pin 1 is the first triple gate of 74HCU125 chips
Control terminal, since the output of output end 143 is high level signal, the pin 2 and pin 3 of 74HCU125 chips disconnect,
The pin 2 of 74HCU125 chips is connect with control processor, the pin 3 of 74HCU125 chips and the first pin of multiplex interface 11
111 connections, at this point, control processor can not be communicated by 74HCU125 chips with the first pin 111 of multiplex interface 11.
Similarly, the pin 4 of 74HCU125 chips is connect with output end 143, and pin 1 is the second tri-state of 74HCU125 chips
The control terminal of door, since the output of output end 143 is high level signal, the pin 5 and pin 6 of 74HCU125 chips are disconnected
It opens, the pin 5 of 74HCU125 chips is connect with the second pin 112 of multiplex interface 11, pin 6 and the control of 74HCU125 chips
Processor connects, at this point, control processor can not be led to by 74HCU125 chips and the second pin 112 of multiplex interface 11
Letter.
The pin 10 of 74HCU125 chips is the control terminal of third triple gate, is connect with third pin 113.Since third is drawn
Foot 113 is grounded, therefore the pin 10 of 74HCU125 chips gets low level signal from third pin 113, at this point, 74HCU125
The pin 9 and pin 8 of chip are connected.And the second pin 112 of multiplex interface 11 is connect with the pin 9 of 74HCU125 chips, control
Therefore processor processed is connect with the pin 8 of 74HCU125 chips, IR extended line plugs are needed IR signal transmissions to control process
When device, IR signals can be transmitted to the second pin of the multiplex interface 11 of IR signal connection ends connection by IR signal connection ends
112.The second pin 112 of multiplex interface 11 can be by the pin 9 of IR signal transmissions to 74HCU125 chips.Due to 74HCU125
The pin 9 and pin 8 of chip are connected, thus 74HCU125 chips can by the pin 8 of IR signal transmissions to 74HCU125 chips,
IR signals are transmitted to control processor by 74HCU125 chips 133 by its pin 8.
The pin 13 of 74HCU125 chips is the control terminal of the 4th triple gate, is connect with third pin 113, since third is drawn
Foot 113 is grounded, therefore the pin 13 of 74HCU125 chips gets low level signal from third pin 113, at this point, 74HCU125
The pin 12 and pin 11 of chip are connected.And the pin 12 of 74HCU125 chips is grounded, the control of pin 11 and PNP type triode
End connection, therefore when the pin of 74HCU125 chips 12 and pin 11 are connected, the pin 11 of 74HCU125 chips is grounded, this
When, the control terminal ground connection of PNP type triode, then its first end and second end can be connected in PNP type triode.PNP type triode
First end connect 3.3v power supplys, second end passes through the first pin 111 of resistance R6 and multiplex interface 11, so, 3.3v
Power supply can be that the first pin 111 of multiplex interface 11 is powered, due to the first pin 111 and IR extended lines of multiplex interface 11
The power connector end of plug connects, therefore 3.3v power supplys can be the power connector end power supply of IR extended line plugs.
So, by the open and close of each triple gate of above-mentioned 74HCU125 chips, realize that IR extended lines are inserted
Communication between head and control processor also may be used from while the circuit of multiplexed port can be made to realize the function of serial ports terminal
Ensure that the normal realization of the function of IR extended lines port as completes and serial port circuit is multiplexed to IR extensions in the present invention
Line circuit.
An embodiment of the present invention provides a kind of circuits of multiplexed port, including:Multiplex interface, for connecting external plug;
The multiplex interface includes the first pin, second pin, third pin and the 4th pin;Wherein, the 4th pin is grounded;Third
Pin is connect with first power source unit, and the first pin of multiplex interface, second pin is connect with detection process unit, third pin
It is connect with detection process unit and converting unit, external plug includes serial interface plug or infrared IR extended lines plug;Converting unit
It is connect with detection process unit, the level signal for being transmitted according to the third pin of multiplex interface, carries out signal conversion, and will
The signal of conversion is sent to detection process unit;Detection process unit is connect with control processor, for according to multiplex interface
The level signal of third pin transmission, determines the type for the external plug for being inserted into multiplex interface, and is transmitted according to converting unit
Conversion signal, between the first pin and second pin of multiplex interface, control processor carry out signal transmission.In this way,
Multiplex interface in the circuit of multiplexed port through the invention can be connect with external plug.This external plug can be string
Mouth plug can also be infrared IR extended lines plug.That is, the circuit of multiplexed port in the present invention is will to realize serial ports
Circuit multiplexer to realize IR extend line jack circuit.So, at the detection of the circuit of the multiplexed port in the present invention
The difference for the level signal that reason unit is transmitted according to the third pin of multiplex interface, carries out different signal transmissions, so as to
With convenient, the inexpensive purpose that serial ports terminal is realized in DTV STB.
An embodiment of the present invention provides a kind of digital motor top boxs, as shown in fig. 7, comprises:Control processor 701 and port
The circuit 702 of multiplexing.Wherein, the circuit of the multiplexed port described in 702 above-described embodiment of circuit of multiplexed port.
An embodiment of the present invention provides a kind of digital motor top boxs, include the circuit of control processor and multiplexed port,
In, the circuit of multiplexed port includes:Multiplex interface, for connecting external plug;The multiplex interface include the first pin, second
Pin, third pin and the 4th pin;Wherein, the 4th pin is grounded;Third pin is connect with first power source unit, and multiplexing connects
First pin of mouth, second pin are connect with detection process unit, and third pin is connect with detection process unit and converting unit,
External plug includes serial interface plug or infrared IR extended lines plug;Converting unit is connect with detection process unit, for according to multiple
The level signal transmitted with the third pin of interface, carries out signal conversion, and the signal of conversion is sent to detection process unit;
Detection process unit is connect with control processor, and the level signal for being transmitted according to the third pin of multiplex interface is determined and inserted
Enter to the type of the external plug of multiplex interface, and the signal of the conversion according to converting unit transmission, the first of multiplex interface
Pin and second pin carry out the transmission of signal between control processor.In this way, in the circuit of multiplexed port through the invention
Multiplex interface can be connect with external plug.This external plug can be that serial interface plug can also be infrared IR extended lines plug.
That is, the circuit of multiplexed port in the present invention is will to realize that the circuit multiplexer of serial ports extremely realizes that IR extends line jack
Circuit.So, the detection process unit of the circuit of the multiplexed port in the present invention is passed according to the third pin of multiplex interface
The difference of defeated level signal carries out different signal transmissions, inexpensive in DTV STB so as to convenient
The middle purpose for realizing serial ports terminal.
Finally it should be noted that:The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations;Although
Present invention has been described in detail with reference to the aforementioned embodiments, it will be understood by those of ordinary skill in the art that:It still may be used
With technical scheme described in the above embodiments is modified or equivalent replacement of some of the technical features;
And these modifications or replacements, various embodiments of the present invention technical solution that it does not separate the essence of the corresponding technical solution spirit and
Range.