JP2000298538A - Interface device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interface device preventing a down port from being uselessly utilized by making it possible to directly connect a device to the down port without passing an interface conversion circuit even in the case of the down port capable of connecting the device through the interface conversion circuit. SOLUTION: A down port 4 for a universal serial bus(USB)-HUB 1 is provided with USB connectors 7-1, 7-2 for connecting a device through a USB and connecting connectors 8-1, 8-2. Interface conversion circuits 9-1, 9-2 respectively convert the connectors 8-1, 8-2 into interfaces corresponding to devices connected from the USB. Each of connection equipment switching parts 10-1, 10-2 connects one of devices connected to the connectors 7-1, 7-2 to the down port 4. Therefore the down port 4 can be effectively utilized without uselessly utilizing it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interface device used when an information processing device such as a personal computer is used as a host device, and a keyboard, a mouse, a printer, a scanner and the like are connected to the host device as a device device. (Universal Seri
al Bus) relates to an interface device for connecting a device device to a host device.

[0002]

2. Description of the Related Art Conventionally, a personal computer (hereinafter, referred to as a PC) has a keyboard, a mouse, a printer,
Connect device devices such as scanners and digital cameras,
Various things are performed on a PC using these device devices. Until now, interfaces for connecting device devices to PCs include SCSI and RS-232.
However, these devices could not be used on the PC by simply connecting the device to the PC with a cable in these interfaces (necessary for operating the connected device). Software (drivers, etc.) must be installed on the PC.) For this reason, there is a problem that the work of connecting the device device to the PC is troublesome.

Therefore, recently, a function of automatically installing software such as a driver necessary for operating the device by recognizing the connected device by simply connecting the PC and the device with a cable or the like. (So-called plug-and-play function) has been proposed, and USB (Universal) is used as an interface to realize this function.
al Serial Bus) has been developed.

A USB-HUB has already been proposed as an interface device for increasing the number of ports when connecting a device to a PC by USB. A general USB-HUB is provided with an up port for connecting a host device (PC) and a plurality of down ports for connecting device devices. Recently, some of the down ports are connected to a non-USB interface (RS-232).
C, SCSI, IDE, etc.) so that device devices can be connected to the down port via an interface conversion circuit.
-HUB has also been proposed.

[0005]

However, in the conventional hybrid USB-HUB, a USB interface device cannot be connected to the down port for connecting the device via the interface conversion circuit. Was. That is, a down port for connecting a device via the interface conversion circuit cannot be used as an original USB down port. For this reason, USB
When a user who is connected to a device device not equipped with a USB device attempts to replace the device device with a device device equipped with a USB, the down port cannot be used. That is, there is a problem that the down port is wasted.

[0006] Further, in the conventional USB-HUB, only one PC can be connected to the up port. Therefore, in order to use a device connected to the down port by a plurality of PCs, it is necessary to connect the up port to the up port. There is a problem in that the connection of the PC must be changed, and it takes time to change the wiring.

SUMMARY OF THE INVENTION An object of the present invention is to prevent a down port from being wasted by allowing a device to be directly connected to a down port without using an interface conversion circuit. An object of the present invention is to provide an interface device.

It is another object of the present invention to provide an interface device that can easily use a device connected to a down port by a plurality of host devices.

[0009]

(1) An interface device according to the present invention includes an up port to which a host device is connected and a plurality of down ports to which device devices functioning as peripheral devices of the host device are connected. , For at least one of said downports, a first
A first connector for connecting the device with the second interface, a second connector for connecting the device with the second interface, and interface conversion means for converting the first interface into the second interface. At the same time, the first connector is directly connected to the down port, and the second connector is connected to the down port via the interface conversion means (claim 1).

[0010] In this configuration, the second connector connected to the down port via the interface conversion means and the first connector directly connected to the down port are provided. For this reason, by using the second connector, the device can be connected to the down port via the interface conversion circuit, and by using the first connector, the device can be directly connected to the down port. can do. For example, the device can be connected to the down port by USB, or can be connected by an interface other than USB. Therefore, any user can effectively use the down port.

(2) detecting means for detecting whether or not a device is connected to the first connector; and, if a device is connected to the first connector, the first connector is connected to a down port. Switching means for connecting the second connector to the down port via the interface conversion means if the device is not connected to the first connection part (claim 2).

With this configuration, it is detected whether or not a device is connected to the first connector. If the device is connected to the first connector, the first connector is connected to the down port, and the first connector is connected to the down port. If no device is connected to the connector, the second connector is connected to the down port via the interface conversion means. That is, the device connected to the down port can be automatically switched.

(3) The first interface is a US interface
B (Universal Serial Bus) (claim 3).

In this configuration, a USB-equipped device can be connected to an information processing device such as a personal computer, so that work such as installation of software (eg, a driver) necessary for operating the connected device is unnecessary. Thus, connection of device devices can be easily performed.

(4) An up port to which a host device is connected and a plurality of down ports to which device devices functioning as peripheral devices of the host device are connected, and a plurality of host devices to which the host device is connected to the up port. And a switching means for switching a connector to be connected to the up port from among the plurality of connectors (claim 4).

In this configuration, an arbitrary connector among the plurality of connectors can be connected to the up port. That is, a host device is connected to each of a plurality of connectors, and a host device that uses a peripheral device connected to a down port can be changed by switching a connector connected to an up port. Therefore, the device connected to the down port can be easily switched and used by a plurality of host devices.

(5) The switching means includes means for connecting the connector not connected to the up port to the down port.

In this configuration, a host device connected to a connector not connected to the up port is connected to the down port. Therefore, the host device connected to the up port can use the device connected to the down port as a device device. That is, it is possible to configure a network in which communication can be performed between devices connected to a plurality of connectors that can be connected to the up port.

[0019]

FIG. 1 is a diagram showing a configuration of a hybrid USB-HUB according to an embodiment of the present invention. In the figure, reference numeral 1 denotes a USB-HUB main body. 2
Is a HUB controller for controlling the operation of the main body;
The UB controller 2 has an up port 3 to which a personal computer (hereinafter, referred to as a PC) is connected as a host device, and a down port 4 (4-1 to 4) for connecting a device device to the host device connected to the up port 3.
-4) is provided. 5 (5-1, 5-2) is a personal computer (hereinafter, PC) connected as a host device.
Say ) Is a host connector. Reference numeral 6 denotes a host switching unit for connecting one of the PCs connected to the host connectors 5-1 and 5-2 to the up port 3.
Note that a PC connected to the up port 3 operates as a host device.

The down ports 4-1 4-2, and 4-3 are respectively provided with USB connectors 7 for connecting device devices equipped with USB (first interface).
-1, 7-2, and 7-3 are connected. Reference numerals 8-1 and 8-2 denote connection connectors for connecting the device with an interface (second interface) such as RS-232C or SCSI, which is different from USB, and reference numerals 9-1 and 9-2 denote connection connectors. Conversion between the interface of the device connected to the connectors 8-1 and 8-2 and USB (for example, USB-to-Ser)
ial conversion, USB-to-Parallel conversion, U
This is an interface conversion circuit that performs SB-to-Ethernet conversion.

As described above, the down ports 4-1 and 4-2
Has USB connectors 7-1 and 7-2 and a connector 8-
1, 8-2 are connected. On the other hand, since it is not possible to simultaneously connect and use a plurality of device devices with a single down port, device devices are connected to the USB connector 7-1 (7-2) and the connection connector 8-1 (8-2). When is connected, one of them is down port 4-1 (4-2)
And the other end must be disconnected from the down port 4-1 (4-2). This switching is performed by the connection device switching units 10-1 and 10-2. A conversion circuit 11 is connected to the host connectors 5-1 and 5-2, and is used to connect one PC not connected to the up port to the down port 4-4. This is a conversion circuit that performs USB conversion. Thereby, the host connector 5
-1, 5-2 is connected to the down port 4-4, so that the other PC connected to the up port
Can use one PC connected to the down port 4-4 as a device. That is, the PCs connected to the host connectors 5-1 and 5-2 can be connected via a pseudo network.

In FIG. 1, a portion A surrounded by a broken line is a configuration according to claims 1 to 3 of the present invention, and a portion B is a configuration according to claims 4 and 5 of the present invention.

Hereinafter, the USB-HU according to this embodiment will be described.
The operation of B1 will be described. First, down port 4-1
The operation according to (or 4-2) will be described. FIG. 2 is a diagram illustrating the operation of the connected device switching unit. As shown in FIG. 2, the connection device switching unit 10 is connected to the down port 4-1 (or 4).
-2) is a switch circuit for connecting either the USB connector 7 or the interface conversion circuit 9. That is, switching is performed so that one of the device devices connected to the USB connector 7 or the connection connector 8 is connected to the down port 4. USB of this embodiment
In the HUB 1, if a device device is connected to the USB connector 7, the device device is connected to the down port 4. If the device device is not connected to the USB connector 7, the device is connected via the interface conversion circuit 9. The device connected to the connector 8 is connected to the down port 4. When no device device is connected to both the USB connector 7 and the connection connector 8, the connection device switching unit 10 connects the interface conversion circuit 9 to the down port 4.

As described above, the USB according to this embodiment
In the HUB 1, the connection device switching unit 10 connects the device device to the down port 4 if the device device is connected to the USB connector 7. If the device device is not connected to the USB connector 7, the interface conversion circuit 9 is connected to the down port 4.

Next, referring to FIG. 3 and FIG.
The switching operation of the connected device by the B controller 2 will be described. FIG. 3A is a diagram illustrating a state in which a device connected to the USB connector is connected to the down port, and FIG. 3B is a diagram illustrating a state in which the device connected to the connector is connected. FIG. 4 is a diagram illustrating a state when the device is connected to the down port, and FIG. 4 is a flowchart illustrating a process of switching a device connected to the down port. In the USB, as is well known, device devices are connected by four cables including two data transfer lines (D +, D-) and two power supply lines (V, GND).

As shown in FIG. 3, the connected device switching unit 10 includes a power supply SW 21 for connecting / disconnecting a power supply line to / from a device connected to the USB connector 7 and a device SW connected to the connection connector 8. A power supply SW 22 for connecting / disconnecting the power supply line, a device detection circuit 23 for detecting whether a device device is connected to the USB connector 7, and a U.S.C.
A device switching SW 24 is provided for switching the connection between the device connected to the connector 7 for B or the device connected to the connector 8 for connection via the interface conversion circuit 9.

As is well known, when a device is connected to the USB connector 7, one of D1 + and D1- is pulled up. When no device is connected to the USB connector 7, D1 + is used. And D1-
Are in a Low state. Device detection circuit 23
Constantly monitors the state of D1 + and D1-
When either 1+ or D1- is pulled up, it is determined that the device is connected to the USB connector 7, and the state in which both D1 + and D1- are Low has continued for a predetermined time (several tens of ms). At this time, it is determined that the device connected to the USB connector 7 has been disconnected. Note that D1 + and D1- are both Low.
When the USB connector 7 is
The device connected to the USB connector 7 is not determined to be disconnected because, depending on a signal exchanged between the device connected to the USB connector 7 and the host, both D1 + and D1- are instantaneously connected. This is because the state may be low. The switching of the device switching SW 24 is performed by a control unit (not shown) provided in the connected device switching unit 10.

Hereinafter, the operation of the connection device switching unit will be described with reference to FIG. The connected device switching unit 10 checks whether the device switching SW 24 is connected to the USB connector 7 side (n1). If the device switching SW 24 is connected to the USB connector 7 side, the device detection circuit 23 outputs D1 +
It is monitored that both D1 and D1- become Low (n2). At this time, the power supply line is connected to the USB connector 7 by the power supply SW21.
The power supply line of the interface conversion circuit 9 is disconnected by the power supply SW 22 (see FIG. 3A).
If both D1 + and D1- become low at n2, it is monitored whether this state continues for a predetermined time (several tens of ms) (n3), and if it does not continue for a predetermined time, the process returns to n2. On the other hand, when the state in which both D1 + and D1- are Low continues for a predetermined time, it is determined that the device connected to the USB connector 7 has been disconnected, and the device switch SW24 is switched to the interface conversion circuit 9 (n4). . Then, the power supply line for the interface conversion circuit 9 is connected (the power supply SW 22 is switched) (n5). Thereby, the power supply of the interface conversion circuit 9 is started, and the interface conversion circuit 9 starts operating. At this time,
The power switch 21 is not switched, and the state where the power line is connected to the USB connector 7 is maintained (FIG. 3B).
reference). Then, the process returns to n1, and the above processing is repeated. In this case, the device switching SW24 is switched to n1.
Is not connected to the USB connector 7 side, and the process proceeds to n6 shown below.

At n6, the device detection circuit 23 sets D1 +
Alternatively, it is monitored that one of D1- is in a pulled-up state, and when one of D1 + or D1- is in a pulled-up state (that is, when a device is connected to the USB connector 7). , Power supply SW21 and 2
2 are both disconnected (n7), and the device switch SW24 is set to U
Switch to the SB connector 7 side (n8). As a result, power is not supplied to the interface conversion circuit 9 and the operation of the interface conversion circuit 9 is stopped. And after waiting for several tens of ms,
Only the power supply SW21 is connected (n9, n10) (FIG. 3
The state returns to the state shown in FIG. ).

As described above, the USB-HU of this embodiment
In B1, if a device device is connected to the USB connector 7, the data transfer lines (D +, D-) are connected to the device device connected to the USB connector 7 by the device SW 24, and the USB connector 7 is connected. If no device device is connected to the data transfer lines (D +, D-), the device SW24 connects the connection connector 8 via the interface conversion circuit 9 to the connection connector 8 side.
When no device device is connected to the USB connector 7 and the connection connector 8, the data transfer lines (D +, D-) are connected to the interface conversion circuit 9 side.

That is, the USB-
The HUB 1 detects whether a device is connected to the USB connector 7, and switches the device connected to the down port 4 according to the detection result. Therefore, an RS-232 device different from the USB device is used.
Hybridized USB- with down port that can be connected by C or SCSI interface
Function as HUB, and USB to this down port
Can be connected and used. Therefore, the conventional hybridized USB-H
There is no waste in the down port unlike UB.

Incidentally, recently, the number of users who use the USB has increased as an interface for connecting the device to an interface such as RS-232C or SCSI, so that the device is connected to the USB connector 7. For example, regardless of whether a device device is connected to the connection connector 8, it is better to connect the data transfer lines (D +, D-) to the device device connected to the USB connector 7 (USB connector). It is considered that the user's convenience is better if the device connected to 7 is prioritized). Therefore,
In the above embodiment, when the device is connected to the USB connector 7, the data transfer lines (D +, D−) are connected to the USB connector 7 regardless of whether the device is connected to the connector 8. Side. However, depending on the user's convenience, US
It may be possible to switch between giving priority to the device connected to the connector 7 for B and giving priority to the device connected to the connector 8 for connection.

In the above embodiment, the connection switching unit 10
Is provided with a power supply switch 21 for switching connection / disconnection of the power supply line to / from the USB connector 7.
Numeral 1 is provided to improve reliability at the time of switching when a device is connected to the USB connector 7. Specifically, when a device device is connected to the USB connector 7, the device device is prevented from starting data transmission before the device switching SW 24 is switched. That is, before the switching of the device switching SW24, the power supply line is cut off by the power supply SW21, thereby prohibiting the device connected to the USB connector 7 from starting data transmission.

Further, when the power supply SW22 supplies operating power to each of the device device and the interface conversion circuit 9 when the device device is connected to the USB connector 7 and the connection connector 8, the power supply capacity becomes insufficient. This is provided to prevent a malfunction due to the risk of occurrence. That is, the power supply SW22 is also provided to improve reliability.

In the above embodiment, whether or not a device is connected to the USB connector 7 is determined by monitoring the state of the data transfer lines D1 + and D1-, but is determined from the power supply lines (V, GND). You may do so. FIG. 5 shows the configuration of the connection device switching unit 10 in this case. FIG. 5A is a diagram showing a state in which a device connected to the USB connector is connected to the down port, and FIG. It is a figure showing the state at the time of being connected to a down port. The USB- of this embodiment
In the HUB 1, a power line for a device connected to the USB connector 7 and a power line for a device connected to the connector 8 via the interface conversion circuit 9 are separately provided (power SW2).
1, 22 are not provided. ). However, the connection connector 8 is connected to the down port 4 via the device device connected to the USB connector 7 or the interface conversion circuit 9.
And a device switch SW 24 for switching to connect the device connected to the device. Reference numeral 31 shown in the figure is a current detection circuit for detecting whether or not a current is flowing through a power supply line connected to the USB connector 7.

Referring to FIG. 6, the operation of the connected device switching unit 10 according to this embodiment will be described. FIG.
5 is a flowchart showing the operation of the connection device switching unit 10 according to the embodiment. The connected device switching unit 10 checks whether the data transfer lines (D +, D-) are connected to the USB connector 7 by the device switching SW 24 (n21). The current detection circuit 31 monitors whether the power supply line connected to the USB connector 7 is in a state where no current flows (n22). That is, it monitors whether the device connected to the USB connector 7 is disconnected. When the power supply line is in a state where no current flows (when the device connected to the USB connector 7 is disconnected), the device switching SW
24, the connection of the data transfer lines (D +, D-) to the USB connector 7 is disconnected (n23). At this time, the data transfer line is not immediately connected to the interface conversion circuit 9 side by the device switching SW24, and after waiting for a predetermined time (several tens of ms) (n24), the data transfer line is connected to the interface conversion circuit 9 side. n21
(N25). In this case, in n21, since the data transfer line is not connected to the USB connector 7 side by the device switching SW24, the process proceeds to n26 described below.

At n26, the current detection circuit 31
The power supply line connected to the SB connector 7 is monitored to be in a state where a current is flowing. That is, USB
It monitors that a device is connected to the connector 7 for use. When the power supply line is in a state where a current is flowing (when a device is connected to the USB connector 7), the data transfer lines (D +, D-) with the interface conversion circuit 9 are switched by the device switching SW24. The connection is disconnected (n27). Also at this time, the device switching S
By W24, the data transfer line is not immediately connected to the USB connector 7 side, and after waiting for a predetermined time (several tens of ms) (n28), the data transfer line is connected to the USB connector 7 side and the process returns to n21 (n29). ).

As described above, the USB-HU of this embodiment
In B1, it is determined from the state of the power supply line connected to the USB connector 7 whether or not a device is connected to the USB connector 7, and the down port 4
Switching to connect a device connected to the connector 7 for B or a device connected to the connector 8 for connection via the interface conversion circuit 9 is performed.

Next, the operation of switching the host device in the USB-HUB 1 of this embodiment will be described.
FIG. 7 is a diagram illustrating an operation of switching the host device. As described above, the USB-HUB1 of this embodiment
Has two connectors (host connector 5) for connecting a host device (PC), and can connect two PCs. As is well known, in the USB, a plurality of PCs cannot be a host device at the same time, so one of the PCs connected to the host connector 5 is connected to the up port 3 as a host device. As shown in FIG. 7, the switching of the host device is performed in sw1. FIG. 7A shows a state in which a PC connected to the host connector 5-1 is a host device, and FIG. 7B shows a state in which a PC connected to the host connector 5-2 is a host device. It is the state at the time. An operation switch is provided on the USB-HUB1 main body, and the user can freely perform the above switching by using the operation switch.

As described above, the USB according to this embodiment
In -HUB1, the user can freely select a PC to function as the host device from the PCs connected to the two host connectors 5 by a simple operation of switching a switch. Therefore, the two PCs can easily share the device connected to the down port 4 without performing troublesome operations such as changing the wiring of the device connected to the down port 4.

Further, the USB-HUB1 of this embodiment
The PC connected to the host connector 5-1 (or 5-2) and not connected to the up port 3 is connected to the down port 4-4 via a conversion circuit (USB-to-USB).
The connection to connect to is performed. Note that sw1 and sw
2 is a switch that operates in conjunction. At this time, one PC connected to the down port 4-4 functions as a device of the other PC connected to the up port. That is, a network is established between the two PCs connected to the host connector 5, and information communication can be performed between the two PCs.

In the above embodiment, the device connected to the USB connector 7 is preferentially connected to the down port 4, but the device connected to the connector 8 is preferentially connected to the down port 4. May be connected. In this embodiment, the USB-HU
The above description has been made by taking an example in which B1 has four down ports 4, but the number of down ports may be four or more. Also, the connection device switching unit 10
Are provided in the two down ports 4-1 and 4-2, but may be provided in all the down ports 4 or may be provided in only one down port 4.
Also, in this embodiment, the device device is set to U
Although the USB-HUB 1 connected by SB has been described as an example, the present invention can be applied not only to USB but also to an interface device that connects device devices with other interfaces.

[0043]

As described above, according to the present invention, the second connector to which the device is directly connected is provided to the down port to which the device can be connected via the interface conversion circuit. Therefore, device devices can be connected via an interface conversion circuit, or can be directly connected without an interface conversion circuit. Therefore, any user can effectively use the down port without wasting it.

Also, it is detected whether or not a device is connected to the first connector. If the device is connected to the first connector, the first connector is connected to the down port, and the first connector is connected to the down port. If the device is not connected to the down port, the second connector is connected to the down port via the interface conversion means, so that the device connected to the down port can be automatically switched.

Also, since the USB-equipped device can be connected to an information processing device such as a personal computer, it is not necessary to install software (eg, a driver) necessary for operating the connected device. Thus, connection of device devices can be easily performed.

Further, since an arbitrary connector among the plurality of connectors can be connected to the up port, by connecting a PC to each of the plurality of connectors, the connector to be connected to the up port is switched. With this simple operation, the host device that uses the device connected to the down port can be changed.

Further, since the host device connected to the connector not connected to the up port is connected to the down port, the host device connected to the up port is connected to the host device connected to the down port. Can be used as a device. Therefore, it is possible to configure a network in which communication can be performed between devices connected to a plurality of connectors that can be connected to the up port.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a hybridized USB-HUB according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating switching of a device connected to a down port.

FIG. 3 is a diagram illustrating switching of a device connected to a down port.

FIG. 4 is a flowchart illustrating an operation of switching a device connected to a down port.

FIG. 5 is a diagram illustrating switching of a device connected to a down port according to another embodiment.

FIG. 6 is a flowchart illustrating an operation of switching a device connected to a down port according to another embodiment.

FIG. 7 is a diagram illustrating switching of a host device connected to an up port.

[Explanation of symbols]

 1-USB-HUB 2-HUB controller 3-Up port 4 (4-1 to 4-4) -Down port 5 (5-1, 5-2) -Host connector 6-Host switching unit 7-USB connector 8 (8-1, 8-2)-Connector for connection 9 (9-1, 9-2)-Interface conversion circuit 10 (10-1, 10-2)-Connection device switching section 11-Conversion circuit 23-Device Detection circuit 24-Device switching SW 31-Current detection circuit

Claims (5)

[Claims] An up port to which a host device is connected and a plurality of down ports to which a device functioning as a peripheral device of the host device are connected, and at least one of the down ports has a first port. A first connector for connecting the device with the second interface, a second connector for connecting the device with the second interface, and interface conversion means for converting the first interface into the second interface. An interface device, wherein the first connector is directly connected to the down port, and the second connector is connected to the down port via the interface conversion means. 2. A detecting means for detecting whether a device device is connected to the first connector, and connecting the first connector to a down port if a device device is connected to the first connector. And the first
2. The interface device according to claim 1, further comprising switching means for connecting the second connector to the down port via the interface conversion means if no device device is connected to the connection part. 3. The method according to claim 1, wherein the first interface is a USB.
The interface device according to claim 1, wherein the interface device is (UniversalSerial Bus). 4. An up port to which a host device is connected and a plurality of down ports to which device devices functioning as peripheral devices of the host device are connected, and a plurality of host devices connecting the host device to the up port. An interface device comprising a connector, and switching means for switching a connector to be connected to an up port from among the plurality of connectors. 5. The interface device according to claim 4, wherein said switching means includes means for connecting said connector not connected to an up port to said down port.