JP2003271270A - Device equipped with interface recognition function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device equipped with a recognition function which can easily recognize which is used a host device or a peripheral device by the use of a connector of an existing interface. <P>SOLUTION: A CPU 30 detects voltage supplied from a personal computer 8 and recognizes that the personal computer 8 is connected when a voltage value is higher than 4.75 V. When the voltage value is lower than 4.75 V, the CPU supplies a voltage of 5 V to a digital camera 20, and recognizes that the digital camera 20 is connected if the voltage value of a data signal transmitted from the digital camera 20 is higher than 2 V. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device with an interface recognition function, and more particularly to a device with an interface recognition function which is a peripheral device to which a host computer and peripheral devices can be connected.

[0002]

2. Description of the Related Art Conventionally, as means for connecting a host device and various peripheral devices, in addition to a serial interface and a parallel interface, a USB (Universal Serial Bus) and IEEE capable of supporting a wide range of peripheral devices in recent years have been used.
New interfaces such as 1394 are known.

Some of the peripheral devices are provided with connectors corresponding to an interface for connecting to the host device and an interface for directly connecting another peripheral device.

However, in the data communication performed between the host device and the peripheral equipment as described above and between the peripheral equipment, the communication protocol and the like are different. Therefore, in the peripheral device as described above, it is necessary to recognize which of the host device and the peripheral device is connected in order to reliably transmit and receive data.

Therefore, a device with an interface recognition function, which is a peripheral device capable of recognizing whether a host device or a peripheral device is connected, has been conventionally known.

Such a device with an interface recognition function is provided with a connector into which a connector of a cable is inserted to electrically connect with an external device such as a host device or a peripheral device. A recognition terminal for recognizing the type of interface is provided on the connector of the device and the connector of the cable that is inserted into the device with the interface recognition function. Further, each recognition terminal provided in these connectors, when the connector of the cable is inserted into the connector of the device with the interface recognition function,
The respective recognition terminals are open or short-circuited.

When the external device is connected to the device with the interface recognition function via a cable, the device with the interface recognition function detects whether each of the recognition terminals is open or short-circuited, and is connected according to the detection result. The external device is a host device or a peripheral device.

[0008]

However, in order to recognize whether the external device connected by the device with an interface recognition function is a host device or a peripheral device, each connector has an interface recognition function. In addition to providing each terminal for electrically connecting the device to an external device and transmitting / receiving a data signal, it is necessary to provide the recognition terminal as described above. Therefore, there is a problem that the number of parts is increased, the assembly process is increased, and the manufacturing cost is increased.

The present invention has been made in view of the above points, and provides an apparatus with an interface recognition function capable of easily recognizing whether a host device or a peripheral device is connected by a connector of an existing interface. The purpose is to provide.

[0010]

In order to achieve the above object, a device with an interface recognition function according to the present invention comprises:
It has one connector corresponding to both the interface of the host device and the interface of the peripheral device, and a CPU that controls each unit, and this CPU detects the voltage supplied from the connected external device, When the value of this voltage is higher than a predetermined value, the external device is recognized as the host device, and when the value of the voltage is lower than the predetermined value, a constant voltage is supplied to the external device. When the voltage value of the data signal transmitted from the external device is higher than another predetermined value, the external device is recognized as the peripheral device.

Here, the predetermined value is set to a value slightly lower than the voltage supplied from the host device, and the other predetermined value is set when the data signal is transmitted from the peripheral device to the device with the interface recognition function. It is set to a value slightly lower than the voltage used for.

According to the apparatus with an interface recognition function of the present invention, the voltage supplied from the host device or the voltage of the data signal transmitted from the peripheral device is detected, and whether or not this voltage is higher than a predetermined value is detected. It is possible to recognize which of the host device and the peripheral device is connected to the device with the interface recognition function by determining. Further, the device with an interface recognition function can be supplied with a voltage from the host device through one connector, and can be supplied with a voltage to the peripheral device through this connector.

Further, another apparatus with an interface recognition function according to the present invention is such that the interface is a USB,
One USB connector that is compatible with both the host device interface and the peripheral device interface is an A series connector.

According to another apparatus with an interface recognition function of the present invention, the voltage supplied from the host device or the voltage of the data signal transmitted from the peripheral device is detected, and whether this voltage is higher than a predetermined value or not. By determining whether or not the host device or the peripheral device is connected to the apparatus with the interface recognition function, it can be recognized. Further, the device with an interface recognition function can be supplied with a voltage from the host device through one connector, and can be supplied with a voltage to the peripheral device through this connector.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an apparatus with an interface recognition function according to the present invention will be described below with reference to FIGS.

FIG. 1 is a circuit diagram showing an electric circuit configuration when a printer as an apparatus with an interface recognition function according to the present embodiment is connected to a host device or other peripheral equipment. As shown in FIG. The printer 1 is provided with a USB connector 2 as an interface.

The connector 2 is a series A connector 2, and the series A connector 5 formed at one end of the USB cable 4 is inserted into the connector 2. Further, the USB cable 4
The series B connector 6 formed on the other end of the connector is inserted into the series B connector 21 formed on the digital still camera 20 as a peripheral device.
As a result, the printer 1 is electrically connected to the digital still camera 20. In addition, each USB connector 2 formed in the printer 1 has a power supply terminal 11, two signal terminals 12 and 13, and G.
An ND terminal 14 is formed, and the printer 1 supplies a voltage of 5V to the digital still camera 20 via a USB power supply distribution circuit 11.
Further, the printer 1 receives the data signal D via the digital still camera 20 and the signal terminals 12 and 13.
+ And D- are transmitted and received. Further, among these signal terminals 12 and 13, the signal terminal 12 for transmitting / receiving the data signal D + is supplied with a voltage higher than 2V when transmitting / receiving the data signal D +.

A personal computer 8 as a host device can be connected to the printer 1 by using another USB cable 16 having A series connectors 17 and 18 formed at both ends. That is, the printer 1 is connected to the personal computer 8
In the case of connecting to, the series A connector 17 formed at one end of the other USB cable 16 is inserted into the series A connector 2 formed in the printer 1,
Series A formed on the other end of this USB cable 16
Connector 18 is inserted into the connector 9 of the series A formed on the personal computer 8. This allows
The printer 1 is adapted to be electrically connected to the personal computer 8. And this printer 1
When the personal computer 8 is connected to the printer 1, the printer 1 is configured to be supplied with a voltage of 5 V from the personal computer 8 via the power supply terminal 11, and the printer 1 is Data signals D + and D- are transmitted / received to / from the personal computer 8 through the signal terminals 12 and 13.

Further, the printer 1 has a C controller for controlling the USB controller 28 and each unit of the printer 1.
PU30 is installed. The USB controller 28 receives the data signals D +, D- from the personal computer 8 or the digital still camera 20, compares the data signals D +, D- to determine the signal state, and then the data signal D is transmitted to the CPU 30. The USB controller 28 also receives the data signal D transmitted from the CPU 30, and converts the data signal D into the data signal D + and the data signal D.
It is converted to − and transmitted to the personal computer 8 or the digital still camera 20 via the signal terminals 12 and 13. Further, when the personal computer 8 is connected to the printer 1, the CPU 30 is supplied with a voltage of 5 V from the computer 8 via the power supply distribution circuit 11, while the digital still camera 20 is connected. In this case, a voltage of 5V is supplied to the digital still camera 20 via the power supply distribution circuit 11.

Next, the operation of this embodiment will be described.

As shown in the flow chart of FIG. 2, first, when the printer 1 is turned on, the CP of the printer 1 is
U30 is the power supply terminal 11 of the connector 2 of series A
The voltage supplied from the external device connected via the is detected, and it is determined whether this voltage is higher than a predetermined value of 4.75 V (ST1). At this time, when the personal computer 8 is connected to the printer 1 as an external device, a voltage of 5 V is supplied from the personal computer 8 via the power supply terminal 11 of the connector 2. Therefore, when the detected voltage is higher than 4.75 V (YES in ST1), the voltage is supplied from the personal computer 8, and therefore it is recognized that the personal computer 8 is connected (S).
T2).

On the other hand, the power supply terminal 11 of the connector 2
When the voltage supplied from the device is lower than 4.75 V (NO in ST1), the CPU 30 supplies the voltage of 5 V to the power supply terminal 11 of the connector 2 of the series A (ST3). At this time, if the digital still camera 20 is connected to the printer 1 as an external device,
The digital still camera 20 has the power supply terminal 1
When a voltage of 5V is supplied from the printer 1 via 1,
The connection to the printer 1 is sensed, and the signal terminal 1
The data signals D + and D- are transmitted via 2 and 13. At this time, the data signal D + is transmitted with a voltage higher than 2V.

After that, the voltage supplied from the signal terminal 12 of the connector 2 is detected, and this voltage is a predetermined value 2.
It is determined whether the voltage is higher than V (ST4), and when the detected voltage is higher than 2V (YES in ST4),
Since the data signal D + is transmitted from the digital still camera 20, it is recognized that the digital still camera 20 is connected (ST5).

On the other hand, when the voltage supplied from the signal terminal 12 of the connector 3 is lower than 2V (NO in ST4), it is judged that neither the personal computer 8 nor the digital still camera 20 is connected, 5 to the power supply terminal 11 of the connector 2 of the series A
The V voltage supply is terminated (ST6). Then, after the voltage supply to the power terminal 11 of the connector 2 is completed, the above-mentioned operation is repeated again.

Further, even after the printer 1 recognizes that the digital still camera 20 is connected (ST2) or the personal computer 8 is connected (ST5), the above operation is repeated. . As a result, even when the connection of the personal computer 8 or the digital still camera 20 is released, when the printer 1 is in the ON state, either the personal computer 8 or the digital still camera 20 is always in the printer 1. It can recognize whether it is connected.

According to this embodiment, the voltage supplied to the power supply terminal 11 of the series A connector 2 is detected, and it is determined whether the voltage is higher than a predetermined value of 4.75V. The printer 1 by detecting the voltage supplied to the signal terminal 12 of the connector 2 by supplying a voltage to the power supply terminal 11 of the printer 2 and determining whether this voltage is higher than a predetermined value of 2V. It is possible to recognize whether the personal computer 8 or the digital still camera 20 is connected.

Further, the printer 1 is supplied with a voltage of 5 V through the power supply terminal 11 of one connector 2, and the power supply terminal 1 is instructed by the CPU 30.
It is possible to supply a voltage of 5V to the digital still camera 20 via 1.

Therefore, it is possible to easily recognize which of the personal computer 8 and the digital still camera 20 is connected by the electric circuit in the CPU 30 of the printer 1 by using the existing USB connector. As a result, between the printer 1 and the personal computer 8 or between the printer 1 and the digital still camera 20.
Data signals can be reliably transmitted and received between them. Therefore, the number of parts of the printer 1 is reduced, the assembly process is reduced, and the manufacturing cost can be reduced.

Further, the printer 1 can be electrically connected to both the personal computer 8 and the digital still camera 20 by utilizing one connector 2. That is, in the printer 1, the connector 5 is inserted into the connector 2 of the printer 1 by using the USB cable 4 having the series A connector 5 formed at one end and the series B connector 6 formed at the other end. By inserting 6 into the connector 21 of the digital still camera 20, the digital still camera 20 can be connected. Further, in the printer 1, the connector 17 is inserted into the connector 2 of the printer 1 using the USB cable 16 having the series A connectors 17 and 18 formed at both ends, and the connector 18 is connected to the connector 9 of the personal computer 8. It can also be electrically connected to the personal computer 8 by inserting it.

Further, the digital still camera 20 can be directly connected to the printer 1, and the image data of the photograph taken by the digital still camera 20 can be directly output from the printer 1 to the recording medium. Therefore, it is possible to easily input the image data of the photograph of the digital still camera 20 to the personal computer 8 and then output it by the printer 1, and easily output the image data to the recording medium.

The present invention is not limited to the above embodiment, but various modifications can be made as necessary.

For example, in the present embodiment, the printer 1 is used as the device with the interface recognition function, but the present invention is not limited to this, and other peripheral devices connectable to the host device and the peripheral device may be used. May be. Although the personal computer 8 is used as the host device in the description, the host device is not limited to this and may be a large computer.
Further, the digital still camera 20 has been described as the peripheral device connected to the device with the interface recognition function, but the peripheral device is not limited to this and may be another peripheral device such as a digital video camera.

Although USB is used as the interface, it is not limited to this, and for example, IEEE
Other interfaces capable of connecting between the host device such as E1394 and the peripheral device and between the peripheral devices may be used.

Further, in the present embodiment, the printer 1
Although the series A connector 2 is formed as a USB connector for connecting the personal computer 8 or the digital still camera 20, the present invention is not limited to this. For example, a printer 1 and a personal computer 8 are connected using a USB cable in which a series B connector is formed on the printer, a series B connector is formed on one end, and a series A connector is formed on the other end, and both ends are connected. U with B series connector formed on
The printer 1 and the digital still camera 20 may be connected using an SB cable.

[0035]

As described above, according to the device with interface recognition function of the present invention, which of the host device and the peripheral device is connected by the electric circuit of the CPU by using the connector of the existing interface? Can be easily recognized. As a result, it is possible to reliably transmit and receive the data signal between the device with the interface recognition function and the host device or between the device with the interface recognition function and the peripheral device. Further, by using one connector, it is possible to electrically connect both the host device and the peripheral device.

According to another device with an interface recognition function of the present invention, it is possible to easily recognize which of the host device and the peripheral device is connected by the electric circuit in the CPU using the existing USB connector. can do. As a result, it is possible to reliably transmit and receive the data signal between the device with the interface recognition function and the host device or between the device with the interface recognition function and the peripheral device. Further, a USB cable having a series A connector formed at one end and a series B connector formed at the other end can be electrically connected to a peripheral device, and a series A connector is formed at both ends. It can also be electrically connected to the host device using a USB cable.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an electric circuit configuration of an embodiment of a device with an interface recognition function according to the present invention.

FIG. 2 is a flowchart showing a procedure for recognizing which interface is used in the device with an interface recognition function shown in FIG.

[Explanation of symbols]

1 printer 2 connectors 8 personal computer 9 connectors 11 Power supply terminal 12 signal terminals 20 digital still camera 21 connector 28 USB controller 30 CPU

Claims (2)

[Claims] 1. The system has one connector corresponding to both an interface of a host device and an interface of a peripheral device, and a CPU for controlling each unit.
The PU detects the voltage supplied from the connected external device, recognizes the external device as the host device when the value of the voltage is higher than a predetermined value, and the value of the voltage is the predetermined value. If it is lower than the predetermined value, a constant voltage is supplied to the external device, and if the voltage value of the data signal transmitted from the external device is higher than another predetermined value, the external device is recognized as the peripheral device. A device with an interface recognition function, which is characterized in that 2. The interface is a USB, and one USB connector corresponding to both the interface of the host device and the peripheral device interface is A
The device with an interface recognition function according to claim 1, wherein the device is a series connector.