JPH11282769A - Information input/output terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information input/output terminal equipment which can easily restore a so-called universal serial bus(USB) where communication is stopped. SOLUTION: This equipment for transmitting an information signal through the so-called USB standard, which discriminates connection/non-connection of an information input/output terminal since a data line 11 become a high level to a host computer is provided with a pull-up resistor 4 for pulling up a data line 11 up to a high level, a switch 1 for opening and closing a path for pulling up the data line 11 and a control part which imitate controls state in which this information input terminal is non-connected to the bus by opening the switch 1 and making the data line 11 not high level even if the information input/output terminal is in state where it is connected to the bus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information input / output terminal device for controlling a bus for transmitting an information signal to a host computer.

[0002]

2. Description of the Related Art Conventionally, keyboards, mice, speakers,
A relatively low-speed information input / output terminal device such as a modem and a printer and a host computer (Ho
USB (Universa) as a bus that unifies connections with the same computer and the same connector and cable.
l Serial Bus) standards are provided.

According to the USB standard, it is possible to logically connect up to 127 functions as information input / output terminal devices to one host. Also, the host and the function can be connected in a star configuration via a hub.

[0004] In the USB standard, data transfer speeds of up to 12 MB / sec and 1.5 MB / sec are mixed, and a host and a function are connected in half-duplex. There are also control transfers that are used to initially configure the device.

[0005] The USB standard data transfer method includes an interrupt transfer used when the data amount is small and data loss is not allowed, such as key input, and when the data amount is large and data loss is not allowed, such as a printer output. There are a bulk transfer used and an isochronous transfer used when a relatively large amount of data such as audio and moving images is used to secure a constant transfer rate.

[0006] In recent years, in the field of information input / output terminal devices that communicate using USB, an operating system (Operating System) that controls USB has not been perfect yet. That is, the USB communication may be stopped because the specifications of the operating system do not match (meet) the hardware of the terminal device, there is a bug in the software, or malfunction due to noise or the like. For this reason, there has been a demand for a means that can easily recover when USB communication is stopped.

[0007] Under such circumstances, when communication using the USB standard is stopped, conventionally, a host computer to which the USB is connected is restarted or a connection of a USB root hub of the host computer is disconnected and reconnected. Had been restored.

[0008]

However, in an information input / output terminal device that communicates via USB, when USB communication stops, the host computer restarts the U / O.
When the SB is restored, it takes a long time to restore the work, and the work used so far is not saved, so the work has to be started from the beginning.

Further, when the USB communication is stopped, when the root hub is restored by removing and inserting the root hub, it is necessary to disconnect the connection by, for example, putting a hand behind the housing of the host computer. In addition, when the connection is reinserted into the host computer, there is a problem that the insertion port is not visible and the connection is difficult.

[0010] Furthermore, a user who cannot know how to process when the host computer goes out of control due to the stoppage of communication according to the USB standard spends wasteful time and money, such as making a service call or taking it for repair. .

Accordingly, the present invention has been proposed in view of the above-mentioned conventional circumstances, and can easily recover with a short waiting time even if communication stops or a host computer runs away due to communication stop. It is an object of the present invention to provide an information input / output terminal device capable of performing such operations.

[0012]

In order to solve the above-mentioned problems, an information input / output terminal according to the present invention uses a bus whose connection / disconnection is distinguished by the potential of a data line. An information input / output terminal device for transmitting an information signal to a host computer, comprising potential control means for distinguishing connection / disconnection of the bus to / from the information input / output terminal device by a potential of the data line. Has a potential control means for simulating a state in which the bus is not connected to the information input / output terminal device by a button operation of the user even when the terminal is connected to the information input / output terminal device.

The information input / output terminal device according to the present invention has a function of cutting off the pull-up during operation and forcibly restarting.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an information input / output terminal device according to the present invention will be described below in detail with reference to the drawings.

First, a first embodiment of the information input / output terminal device will be described with reference to FIG. The information input / output terminal device is a terminal device of a host computer for inputting / outputting information, such as a keyboard, a mouse, a speaker, a modem, and a printer, and is a so-called USB (Universal Serial Bus) standard bus. Is connected to the host computer.

The information input / output terminal device has an upstream connector 2 for transmitting an upstream (Up Stream) which is a stream from the terminal device to the host computer.

The upstream connector 2 is connected to Vbus
, A D + terminal 2b and a D− terminal 2c to which the D + line 11 and the D− line 12, which are data lines, respectively, are connected, and a GND terminal 2d to which a GND line is connected. I have. Note that the data line, the D + line, etc.
Reference will be made regardless of whether the information input / output terminal device is inside or outside.

D + terminal 2 of upstream connector 2
b and the D- terminal 2c are connected to the U + which controls the USB by the D + line 11 and the D- line 12, which are data lines.
Each is connected to the SB controller 11. The USB controller 11 controls the USB,
For example, it is provided as a one-chip IC.

The wiring between the upstream connector 2 and the USB controller 3 in the information input / output terminal device is the same in other embodiments, and therefore, the same reference numerals are used in the following description. Will be omitted.

Data lines D + lines 11 and D
The line 12 is used to determine connection / disconnection of the information input / output terminal device to / from the USB; Normally, the D- line 12 is pulled up in a low-speed terminal device (Low Speed Device), and the D + line 11 is pulled up in a 3.3-V power line with a 1.5 kΩ resistor in a high-speed terminal device (High Speed Device). (Pull Up) and the level becomes high.

The host computer to which the USB is connected determines connection / disconnection of the information input / output terminal device to / from the USB based on the level of the data line. That is, U
When connected to the information input / output terminal device, the data line D + line 11 or D- line 12 included in the SB is pulled up to a high level. Therefore, the host computer recognizes the connection of the information input / output terminal device to the USB when the data line goes high.

The first embodiment of the information input / output terminal device comprises an upstream connector 2, a USB controller 3, and a resistor 4 for pulling up a data line of UEB.
And a switch 1 for controlling the pull-up of the data line by the resistor 4.

The switch 1 connected to the 3.3V power supply line and the resistor 4 connected to the D + line 11 are connected in series. Normally, since the switch 1 is closed, when the information input / output terminal device is connected to the USB cable, the D + line 11, which is the data line, is pulled up by the resistor 4 and becomes a high level.

As described above, the host computer
The connection of the information input / output terminal device to the USB is recognized by detecting that the data line D + line 11 has become high level.

Conversely, the host computer detects that the USB data line is no longer at a high level, and thereby detects that the USB cable has been disconnected from the information input / output terminal device and the USB has been disconnected from the terminal device. recognize.

In other words, by setting the data line not at the high level in the information input / output terminal device, it is possible to simulate the host computer with the USB cable disconnected from the terminal device.

In this first embodiment, the data line is pulled up from the power supply line by the resistor 4 or the data line is disconnected just before the resistor 4 by cutting off the data line. In this case, the host computer can recognize that the information input / output terminal device is not connected.

In an information input / output terminal device that communicates using USB, an operating system (Operating System) for controlling USB is not yet perfect, and the hardware of the terminal device matches (meets) the specifications. USB communication may be stopped due to lack of communication, bugs in software, noise jumping in, or the like.

In the first embodiment, when the USB communication is stopped, the switch 1 is opened to stop the pull-up from the power supply line to the D + line 11 via the resistor 4, and the high level is established by the pull-up. D +
Line 11 is not high.

As described above, the host computer is
+ Detects that line 11 is no longer at a high level,
It recognizes that the information input / output terminal device is no longer connected to the USB. That is, a state in which the USB cable is disconnected from the terminal device is simulated by not pulling up the data line.

Therefore, it is possible to cope with the stop of the USB communication without actually disconnecting the USB cable from the terminal device.

Here, if the switch corresponding to the connection / disconnection of the USB cable is quickly opened and closed, a malfunction may occur. Therefore, it is preferable to reconnect the USB cable after a certain time has elapsed.

Therefore, the operation of the switch 1 simulating the connection and disconnection of the USB cable, that is, "open" of the switch 1 corresponding to the state where the USB cable is disconnected, and "close" of the switch 1 corresponding to the state where the USB cable is connected. Regarding (1) and (2), it is preferable that the transition of the switch 1 from “open” to “close” be performed after a certain time has elapsed.

If the USB malfunctions, a terminal device such as a keyboard cannot be used. For this reason, when the USB is stopped, the switch 1 cannot be accessed by software on the host computer side.

Therefore, when the USB malfunctions, the switch 1 needs to be manually opened and closed on the information input / output terminal connected to the host computer via the USB.

For this reason, in the first embodiment,
The information input / output terminal device includes a button (not shown), and when this button is pressed, the switch 1 is opened.

When the USB communication is stopped, the switch 1 is once opened by pressing the button 1 by the user. Thus, the pull-up for the data line is controlled on the terminal device side.

In addition, the system can be restarted by turning off the pull-up during operation and forcibly restoring.

In the other embodiments, a series of steps for restoring a stopped USB is the same as the above-described series of procedures, and therefore, a description of the restoration procedure will be omitted below except for necessary parts. I will.

Although the above-mentioned button is provided in the information input / output terminal device in other embodiments, a brief explanation is omitted.

Next, a second embodiment of the information input / output terminal device according to the present invention will be described with reference to FIG.

In the second embodiment of the information input / output terminal device, an upstream connector 2 to which an upstream bus is connected, a USB controller 1 for controlling USB, and a switch for opening and closing a current from a power supply line to a data line. A transistor 5 serving as a switching element, a resistor 4 connected between the transistor 5 and the data line, and a resistor 7 connected in series between the power supply line and the switch 1 to apply a divided potential to the base of the transistor 5; 8 is provided.

The transistor 5 is a switching element that switches the current supplied from the power supply line to the D + line 11 via the pull-up resistor 4 by the switch 1. The transistor 5 is of an NPN type. The collector is connected to the power supply line, the base is connected to the resistors 7 and 8, and the emitter is connected to the resistor 4.

The switch 1 is connected in series with the resistors 7 and 8, and opens and closes a current from the power supply line to the GND potential. Since the base potential of the transistor 5 changes accordingly, when the button 1 is closed, the transistor 5 is turned off, and when the button 1 is opened, the transistor 5 is turned on.

As described above, in the second embodiment, switching of the transistor 5 by opening and closing the button 1 is performed. Here, when the USB communication is stopped, closing the switch 1 opens a path to the pull-up resistor 4 by the transistor 5, that is, the on / off operation of the switch 1 and the transistor is reversed. This is different from the first embodiment described above.

Next, a third embodiment of the information input / output terminal device according to the present invention will be described with reference to FIG.

In the third embodiment, the power supply line and the GND
Resistor 9 and switch 1 connected in series between
And a logic inverter 8 having an input terminal connected to the resistor 9 and the switch 1, and a resistor 4 connected between an output terminal of the logic inverter 8 and the data line.

In the third embodiment, since the inverter 8 is a logic circuit that outputs an input level and an inverted level, when the switch 1 is opened and a high level is input to the inverter 8, a low level is output. When the switch 1 is closed and a low level is input, a high level is output.

Therefore, when the switch 1 is closed, the high level output from the inverter 8 pulls up the D + line 11 via the pull-up resistor 4, so that the D + line 11 becomes high level.

On the other hand, since the low level is output from the inverter 8 when the switch 1 is open, the D + line 11 does not become high level.

As described above, in the third embodiment of the information input / output terminal device, when the USB communication is stopped, the closed switch 1 is opened so that the D + line is not at a high level. , Can be restored.

Next, a fourth embodiment of the information input / output terminal device according to the present invention will be described with reference to FIG.

In the fourth embodiment, a power supply line and a GN
The resistor 9 and the button 1 connected in series with the D potential
And a mono-multivibrator 10 for generating a single pulse for a predetermined time,
It has a switching unit 11 whose turning-off is controlled, and a resistor 4 connected between the switching unit 17 and the data line.

Here, as the switching unit 17, a semiconductor element such as a transistor or an analog switching relay can be used.

When restoring the stopped USB communication,
When the button 1 is opened, the input of the mono-multi vibrator 10 becomes high level, and a pulse for a certain period is output to the switching unit 11. The switching unit 11 turns off the current from the power supply line to the data line D + line 11 for a certain period of time in response to the pulse from the mono-multi vibrator 10, and does not perform the pull-up to the D + line 11 for a certain period of time. To

According to the fourth embodiment, the button 1
Is closed, for example, after the pull-up of the D + line 11 is turned off for 3 seconds, the D + line 11 is pulled up again. Therefore, a sufficient processing time can be secured on the host computer side, so that malfunction can be reduced.

Next, a fifth embodiment of the information input / output terminal according to the present invention will be described with reference to FIG.

In the fifth embodiment, the data line D +
The line 11 is connected to the power supply line by the pull-up resistor 4, and the resistor 4 and the D
The switch 1 is provided between the positive terminal 2b.

In the fifth embodiment, the USB
If the communication malfunctions, the switch 1 is opened and the pull-up to the D + line 11 connected to the host computer via the D + terminal 2b of the connector 2 is not performed. State.

The host computer recognizes that the USB communication cable has been disconnected from the terminal device because the data line is not at the high level because the pull-up is stopped. Thereby, the USB communication is restored as described above.

The present invention is not limited to the above embodiment. For example, in the above embodiment, the D + line 11 is pulled up among the data lines.
D-line 12 which is a data line other than + line 11
It is needless to say that the present invention can be applied to the case where the pull-up is performed.

As the switch 1, a semiconductor element such as a transistor or an analog switch relay can be used in addition to a mechanical switch.

Further, the data line has a positive logic, that is, goes to a high level when the information input / output terminal device is connected. However, the present invention is not limited to this. The same can be applied to a negative logic data line which becomes low level by providing pull-down means for pulling down to low level instead of pulling up to high level.

As described above, the information input / output terminal device transmits information signals to the host computer via the bus whose connection / disconnection is distinguished by the potential of the data line.

The information input / output terminal device is potential control means for distinguishing connection / disconnection of the bus to / from the information input / output terminal device by the potential of the data line. Even when the terminal is connected to the information input / output terminal device, a state in which the bus is not connected to the information input / output terminal device is simulated by a button operation of the user.

The information input / output terminal has a function of cutting off the pull-up during operation and forcibly restarting.

[0067]

As is clear from the above description, in the present invention, the USB upstream data line is
This simulates a state in which the USB cable is disconnected from the information acquisition terminal device by removing the USB cable from the pull-up by a switch, a semiconductor switch, or a logic circuit.

Therefore, the host computer can easily recover from the information input / output terminal device running away, and the waiting time is short. In addition, service calls from users are reduced, and service costs can be reduced. In addition, reduced user claims can help maintain the credibility of the manufacturer.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a first embodiment of an information input / output terminal device.

FIG. 2 is a block diagram illustrating a configuration of an information input / output terminal device according to a second embodiment.

FIG. 3 is a block diagram illustrating a configuration of a third embodiment of the information input / output terminal device.

FIG. 4 is a block diagram showing a configuration of a fourth embodiment of the information input / output terminal device.

FIG. 5 is a block diagram illustrating a configuration of a fifth embodiment of the information input / output terminal device.

[Explanation of symbols]

1 switch, 2 upstream connectors, 3 U
SB controller, 4 resistors, 11 D + lines

Claims (5)

[Claims] 1. An information input / output terminal device for transmitting an information signal to a host computer via a bus whose connection / non-connection is distinguished by the potential of a data line. Control means for discriminating connection / non-connection to the information input / output terminal device by a button operation of the user even when the bus is connected to the information input / output terminal device. An information input / output terminal device comprising potential control means for simulating a state of non-connection to the information input / output terminal device. 2. The data line potential is at a high level when the information input / output terminal device is connected to the bus, and the potential control means includes a pull-up means for pulling up the data line to a high level; A pull-up switching means for switching the pull-up of the data line by the pull-up means, wherein the pull-up switching means cuts off the pull-up to the data line by the pull-up means, whereby the bus 2. The information input / output terminal device according to claim 1, wherein, even when the information input / output terminal device is in a connected state, a state where the information input / output terminal device is not connected to the bus is simulated by a button operation of a user. Information input / output terminal device. 3. The pull-up means is a resistor for pulling up the data line to a high level, and the pull-up switching means is switching means for opening and closing a path for pulling up the data line by the resistor. 3. The information input / output terminal device according to claim 2, wherein: 4. The apparatus according to claim 2, wherein said pull-up means is a logic circuit connected to said data line, and said pull-up switching means switches between high level / low level output from said logic circuit. Information input / output terminal device. 5. The pull-up means is a resistor for pulling up the data line to a high level, and the pull-up switching means extends from a position on the data line pulled up by the pull-up means to the host computer. 3. The information information input / output terminal device according to claim 2, wherein the terminal is switching means for opening and closing a route.