JP2001222503A - Peripheral equipment control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a peripheral equipment control system, with which the communication path of USB for plural devices can be secured without requiring a large number of end points and complicating a device driver and the existence of a port for debugging maintenance can not be known. SOLUTION: A descriptor switching demand vender request is issued from a device driver 70 to a function 200, when switching is enabled, a device function 40 to be utilized, for example, is switched from print application to a debugging maintenance application and ACK is returned to a host 100 on a status stage. Afterwards, by performing connect signal disconnecting processing and pull-up recovering processing, on the host side, which interprets a new device, the descriptor acquiring operation of the device is performed and a class driver according to the acquired switched device is made active.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting a host to a plurality of peripheral devices (e.g.
The present invention relates to a system for connecting and controlling devices by an al Serial Bus (Al Serial Bus) method, and relates to a system for securing a communication path by a vendor device request transmitted from a host.

[0002]

2. Description of the Related Art USB (Universal Serial Bus) is a peripheral bus specification developed by leaders in the personal computer (PC) and communication (telecom) industries.
USB brings the plug and play capabilities of computer peripherals out of the PC box. According to this specification, a card is inserted into a dedicated computer slot, and the system is reconfigured each time peripheral devices are attached to or detached from a PC.
Eliminates the need for A personal computer equipped with USB can automatically configure the computer peripheral device without the need to reboot or run setup as soon as the computer peripheral device is physically connected. USB allows 12 peripherals, such as monitors and keyboards, to function as additional plug-in sites or hubs simultaneously on a single computer.
Up to seven devices can be run. US
Details of B are described in the Universal Serial Bus Specification, Rev. 1.0 and 199, published July 15, 1996.
It is described in revision 1.1 published August 23, 2008. This specification was jointly published by Compaq, Digital Equipment Corporation, IBM PC Company, Intel, Microsoft, NEC, and Northern Telecom.

Here, the outline of the contents of the USB specification will be described with reference to a USB bus topology. USB connects multiple USB devices to a single USB host. There are two types of USB devices: hub and function
(function). A hub is a device that provides an additional connection point for USB. The function provides the system with functions such as an ISDN connection, a digital joystick, a speaker, a keyboard, and a mouse. In terms of hubs and functions, the USB physical interconnect is a tiered star topology, with the hub being at the center of each star. Each wire segment is a point-to-point connection between (a) a host and a hub, (b) a host and a function, or (c) a hub and another hub or function. FIG. 9 shows the topology of the USB system.
The illustrated USB system has a host 10. Host 10
Has two connection points, port 1 and port 2. Port 2 is connected to function 29 by a wire segment 28. Port 1 is connected to hub 1 by a wire segment 18. Hub 1 has five ports 20. The function 22 is connected to one of these ports by a wire segment 24. Similarly, hubs 2 and 3 are also connected to ports of hub 1. Various functions (e.g., function 3
0, 32, etc.) are connected.

[0004] The hub is a key element in the USB plug and play architecture. The hub functions to simplify the USB connection from the user's perspective and provides robustness at low cost and complexity. The hub is a wiring concentrator that provides the USB multi-connection characteristics. The connection point is called a port (see FIG. 9). Each hub translates a single connection point into multiple connection points. This architecture supports the connection of multiple hubs. Each other downstream port of one hub allows connection to another hub or function. Hubs have USB to each downstream port
Device removal can be detected and these downstream
Power can be distributed to USB devices. Each downstream port is individually enabled and can be configured for either full speed or low speed. The hub sends low-speed ports to full-speed signaling
Disconnect from Function is data or US
This is a USB device that sends and receives control information about B. The functions are typically embodied as independent peripheral devices with cables connected to ports on the hub. However, multiple functions with one USB cable and one embedded hub may be embodied as one physical package. This is known as a composite device. The composite device appears to the host as a hub to which one or more USB devices are fixedly connected. Examples of functions include:
Printer, monitor, mouse, keyboard, audio C
Examples include a PD player, a tape player, and an ISDN connection.

[0005] There is one host on any USB system. US for host computer system
The B interface is called a host controller.
The host controller is embodied in a combination of hardware, firmware, or software.
The root hub is built into the host system and provides one or more connection points. A device endpoint is a uniquely identifiable portion of a USB device (hub or function) that is the source or sink in the communication flow between the host and the USB device. One example of a USB function having two or more endpoints (EndPoint) is a data / voice modem. It has one endpoint for voice packets and one endpoint for data packets.

All bus transactions have a maximum of 3
Involved in the transfer of one packet. Each transaction is
Triggered when the host controller sends a USB packet, USB device address and endpoint number indicating the type and direction of the transaction according to the schedule. This packet is a token packet (T
oken Packet). The USB device specified by this token packet decodes the appropriate address field of the token packet,
Choose yourself. In a transaction,
Data is transferred from the host to the device or from the device to the host. The data transfer method is specified in the token packet. The source of the transaction then sends a data packet indicating whether the transfer was successful. There are four types of transactions. 1
One is used for device configuration or message transfer in control transfer. The second is interrupt transfer, which is used to notify events such as mouse and keyboard. The third is used for bulk transfer in bulk transfer. The fourth is a transfer method that guarantees the delivery time at the expense of the reliability of data transfer in isochronous transfer.

An address is assigned to each function to identify up to 126 functions other than the host. This method of assigning addresses is called bus enumeration. The initial value of the address of the function is 0, and the host performs a setup operation for the device of address 0 and allocates an address while validating one port of each bus in accordance with the topology configured by the hub. In order to set up a function such as bus enumeration, a request from the host is sent from the host to the endpoint 0 of the function by control transfer. A request for such a function is called a device request, and in particular, a standard device request is defined in the USB specification. Each function holds what function it has in a format called a descriptor. The host can read out the contents of the Descriptor by a device request, and change and select the contents. Finally, when the configuration of the function is selected by the SET-CONFIGURATION device request, the configuration of the function other than the endpoint 0 is determined, and the function can be used.

[0008] By the way, in a multifunction peripheral capable of exposing various functions such as a printer function, a scanner function, a facsimile function, and an image data server function, which is called a so-called multifunction copier (MFP), to an external interface, for example,
Parallel (IEEE1284), Serial (RS232C), Ethernet, US
Each function can be accessed from a PC or the like through B, IEEE1394, or the like. In particular, if USB is used as the communication means, the configura which has a description of the interface of multiple device functions (Interface) as the configuration of the Descriptor of the peripheral device
By preparing the option, interactive communication with the PC-side driver / utility can be achieved (hereinafter, this method is referred to as “conventional method 1”). The Descriptor hierarchical structure in this case is described as a hierarchical structure as shown in FIG. 10, for example.
The example shown in FIG. 10 is an example of a printer and has a plurality of printer interface configurations and scanner ports at the interface level. This method is a normal method for realizing a multi-function device in USB. Another alternative is Inte
There is a method of separating the configuration with a scanner from the configuration of a normal printer at the configuration level instead of the rface level (hereinafter, this method is referred to as “conventional method 2”). The Descriptor hierarchical structure in this case is, for example, as shown in FIG.
It is described as a hierarchical configuration as follows. In the configuration shown in FIG. 11, the first configuration is an operation configuration as a normal printer, and the second configuration is for a scanner. This way, unlike the previous method, for the scanner
It is no longer necessary to have EndPoint at all times.

On the other hand, a conventional serial port such as RS-232C or an I / O
A C card was used. For devices equipped with USB for communication with the host, it is conceivable to use USB instead of the conventional communication method not only for the original purpose but also as a method of communicating with the development host and the notebook PC for maintenance. Can be The use of USB eliminates the need for a conventional communication means such as serial for debugging and maintenance, thereby reducing costs. When communication with a debug monitor in a peripheral device or interactive communication with a maintenance program is performed using USB as a communication means, a configuration having an interface description for debugging is performed in the same manner as in the above-described conventional method 1 or conventional method 2. Descriptor
Is prepared as a configuration. That is, a debug port is provided in place of the scanner port in FIG. 9, or a debug / maintenance configuration is provided in place of the scanner configuration in FIG.

[0010]

However, in the case of the configuration as in the conventional method 1, since an endpoint is always prepared for each function, an expensive USB controller having a large number of supported endpoints must be used. , Which increases costs. In the conventional method 2, it is necessary for the host to control which configuration is selected.
The method is difficult. As a device driver on the host side, for example, a printer driver and a scanner driver (or
(For maintenance), there will be configuration conflicts between them. It is necessary to create a mechanism for arbitrating such a state. on the other hand,
In the case where the configuration for debugging / maintenance is provided as in the conventional method 1 or the conventional method 2, in addition to the above-described problem, there is also a problem that the host user is informed of the presence of the debugging / maintenance port. .

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to eliminate the need for many endpoints as in the conventional method 1 and to provide the host-side device as in the conventional method 2. Without complicating the driver, a USB communication path for multiple devices can be secured, and furthermore, the published Descr
It is an object of the present invention to provide a peripheral device control system in which the presence of a debug / maintenance port is not known from iptor. Specifically, a system is provided in which a device descriptor switching request is prepared as a vendor request, and after this request, a bus reset is performed from the host side and setup is performed again to cause another device configuration to occur. To provide. Another object of the present invention is to provide a system in which a function device driver that enables port communication by performing control transfer with a data stage by using transmission and reception vendor requests is provided separately on the host side.

[0012]

According to a first aspect of the present invention, there is provided a peripheral device control system for connecting a host and a peripheral device by a USB system, the device including a device driver having a function of the host issuing a configuration switching vendor request. This is a peripheral device control system characterized by the following.

According to a second aspect of the present invention, in the peripheral device control system according to the first aspect, the host has a device driver for each configuration.

According to a third aspect of the present invention, in the peripheral device control system according to the first or second aspect, the control unit on the peripheral device side having a function of receiving the configuration switching vendor request is a configuration switching vendor. When a request is received, a bus reset or USB cable power-off process is performed, and a descriptor having the switched predetermined configuration is provided to the host side, and the operation state is shifted to an operation state according to the configuration. Is what you do.

According to a fourth aspect of the present invention, in the peripheral device control system according to the third aspect, when it is not possible to shift to an operation state in accordance with the configuration switching request, the control unit on the peripheral device side is provided. It is characterized by returning a rejection response.

According to a fifth aspect of the present invention, in the peripheral device control system according to any one of the first to fourth aspects, one of the switched configurations is a device configuration for debug maintenance communication. Is what you do.

According to a sixth aspect of the present invention, a host and a peripheral device are
In the peripheral device control system connected by the B method,
It is characterized in that the host has a device driver having a function of issuing a transmission and reception vendor request for enabling port communication by control transfer with a data stage.

According to a seventh aspect of the present invention, in the peripheral device control system according to the sixth aspect, the port communication is used for communication for debugging and maintenance.

According to an eighth aspect of the present invention, in the peripheral device control system according to any one of the first to seventh aspects, the peripheral device is a multifunction copier (copy function, printer function,
It is characterized in that it is a function provided in a copier equipped with various functions such as a scanner function, a fax function, an image data server function, and the like.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described based on the following embodiments shown in the accompanying drawings. FIG. 1 is a block diagram showing an outline of a configuration of a peripheral device control system according to the present invention. In the following description, a multifunction device equipped with a printer will be described as an example of a USB function (peripheral device).
The following explanation assumes a PC equipped with Windows 98 as a USB host. The software and hardware configuration of the USB host is specified in Chapter 10 of USB Specification Revision 1.1. As shown in FIG. 1, the hardware 90 of the USB host 100 includes an SIE (Serial Interface Engine) 92 and a USB
It comprises a host controller 91. SIE92 is the part that interprets the differential signal specified in the USB specification.
It is connected to the USB function 200 via a bus (there may be a Hub in the middle). The USB hardware 90 of the USB host 100 is operated by a USB driver 70 having a hierarchical structure. The application 50 communicates with the USB function 200 via the USB driver 70 to achieve the function. The USB function 200 is, for example, a peripheral device such as a multifunction peripheral equipped with a printer. The USB hardware 80 for performing USB communication includes an SIE 82 and a USB function controller 81. USB hardware 80
Are managed by the USB driver 60 and are accessed by the device function 40. For example, in the case of a printer function, the device function 40 performs a printing operation and printer information management. The device function 40 transmits and receives an operation instruction such as a print request from the USB host 100 via the USB driver 60 and data, and performs a desired operation. Do.

FIG. 2 shows the configuration of the USB driver layer on the USB host 100 side. Host side USB driver 70
Is implemented in a hierarchical structure. For example Windows9
8 defines a hierarchical structure of drivers called WDM. The USB hardware 90 is managed by a USB bus class driver 71 in a driver layer constituting the USB driver 70. The USB bus class driver 71 is made as independent of hardware as possible, and has a structure in which hardware-dependent parts are absorbed by a mini driver (MD) (in the case of WDM). In this example, an OHCI MD 76m for managing OHCI type hardware is provided. U
A driver for using the function of each peripheral device connected to the SB is called a class driver. The class driver is implemented in such a way that the functions of the device are as independent of the bus as possible. For example, even if the USB bus class driver becomes a 1394 bus class driver, it is made as unaffected as possible, and the dependent part is also configured to be absorbed by the mini driver (MD). In the example of FIG. 2, the driver for using the device function is St.
reaming class driver 72, HID class driver 73,
The printer class driver 74 and the scanner class driver 77 include a speaker MD 72 m and a mouse as respective MDs.
An MD 73m, a printer MD 74m, and a scanner MD 77m are provided.

Next, an embodiment of a connection control operation to a USB function by a device request (vendor device request) transmitted by a USB host will be described. First, the first connection control method will be described. First
Is a method of preparing a device descriptor switching request as a vendor device request, and after this request, performing a bus reset from the host side and performing setup again to cause a device configuration with another configuration to occur. .
According to this method, there is no need for complicated control on the host side, and only a device driver for each function is prepared, and the functions such as the printer function, the scanner function, and the image data server function have endpoints necessary for all of them. This control can be realized without any problem. In the embodiment shown in FIG. 2, the printer class driver and the scanner class driver have a common endpoint and are class drivers that respond to the switching request. Each of them is created completely independently. It is only necessary to provide a function of transmitting a "switch request".

FIG. 3 shows a vendor device request used in the first connection control method. As shown in FIG. 3, the vendor device request is composed of five fields (this is standardized in the USB specification). First bmReq
uestType indicates a vendor request and the next bR
Identify a specific request with equest. In this case,
0x71 is a “device descriptor switching request”. The printer class driver 74 and the scanner class driver 77 included in the USB driver 70 of the host shown in FIG.
Has the function of sending this request. No special processing is required other than the function of sending the vendor request. Also, each driver operates completely independently and has no mutual relationship.

FIG. 5 shows the configuration of the device driver 60 of the USB function 200. The device driver 60 is a USB Function Controller (hereinafter “UFC”).
The operation is performed via the register 81). Normal UFC8
1 is configured to transmit and receive data for each endpoint (hereinafter abbreviated as EP).
1 and EP2 can perform bulk transfer by DMA. EP0
Is a register access, and the EP0 receives a standard device request, a class device request, and a vendor device request to perform processing. Each EP is managed by the manager layer. They are
An interrupt handler that operates in response to an interrupt from the UFC 81. The EP0 manager 64 interprets the control transfer of EP0. In particular, the management of the descriptor required by the device request is performed by the descriptor management unit 6.
2 is performed. The EP1 manager 64 manages the reception operation by bulk-out transfer and passes the data to the reception data management unit 66. The EP2 manager 65 manages data transfer by bulk-in transfer and transfers data in the transmission data management unit 67. These parts are an I / F abstracted by the USB device I / F 61, a USB print application 41, a USB sc
Communicate with the anner app 43.

The EP0 manager 63 performs control transfer and monitoring of the power line of the USB cable. The monitoring of the power supply line is for monitoring hot plugging and unplugging (plug and play), and the plugging and unplugging of the USB cable is detected based on whether or not there is a Vcc input voltage. The control transfer managed by the EP0 manager 63 includes a standard device request, a class device request, and a vendor device request. FIG. 6 is a flowchart showing a device request process which is a part of the operation of the EP0 manager. In the processing flow shown in FIG. 6, the types of device requests indicated by bmRequestType in the vendor device request (FIG. 3), that is, the standard device request, the class device request, and the vendor device request are determined (S601, S607, S60).
9) The process is performed separately for each device request.

The device request processing operation will be described with reference to the flow of FIG. 6. First, it is checked whether the request is a standard device request (S601). If the request is a standard device request, the contents of the request are GET-Descript.
or request is checked (S602), GE
If the request is a T-Descriptor request, the Descriptor data requested from the descriptor management unit 62 is obtained (S603), and the obtained data is transferred to the USB host 100 as a data stage (S604). The processing is performed (S605). At this time, the descriptor management unit 62 manages tables for two completely different devices (printer and scanner in this example) for the processing of the “first connection control method”, and can switch between them. It has become. As described above, the data of the device selected after the switching is transferred to the USB host 100 as descriptor data requested in the processing of the GET-Descriptor request.

If the bmRequestType of the device request is a vendor device request (S609), the type of the vendor request indicated by bRequest (see FIG. 3) is further identified. As a result of the identification, the vendor request
0x71, that is, when there is a descriptor switching request (S
610), first, the USB device I / F 61 is notified that there is a switching request (S611). USB device I / F
At 61, it is checked whether the state is switchable (S612). If possible, the function of the device being used, that is, the application to be activated, is switched from one of the USB print application 41 and the USB scanner application 43 to the other. Is switched to (S613). Next, switching processing of the descriptor managed by the descriptor management unit 62 is performed (S613). If the processing is successful, the status is returned to the USB host 100 as a status ACK in the status stage (S614).

Thereafter, a connect signal disconnection process is performed (S
615). This is for manipulating the pull-up resistor of the differential signal by hardware, and since this embodiment is a full-speed device capable of bulk transfer, a pull-up resistor is inserted in the D + signal and cut off Execute the process. In the present embodiment, a state in which the cable is pulled out is created by cutting the resistance line once, and the same effect as in the state in which the cable is inserted is obtained by restoring the pull-up thereafter. As a result, the USB host 100 interprets that the connected device has disappeared, and the USB bus driver 70 notifies the class driver of the fact. After that, by restoring the pull-up, the USB host 100 interprets that a new device has been connected, and the descriptor acquisition operation of the device is performed by the USB bus driver 7.
Performed by 0. At this time, since the switched descriptor is obtained, the class driver according to the descriptor is activated. That is, if the descriptor as a printer is provided before the request for switching the descriptor, the host disables the printer class driver 74 in the process of power-off / restoration and replaces the newly provided scanner.
The scanner class driver 77 is enabled according to the port descriptor. In this embodiment, the connection signal disconnection processing is performed by the hardware on the function side. However, there is a method of simulating the disconnection processing by operating the USB bus class driver 71 on the USB host 100 side.

If it is determined in step S612 whether the application is in a switchable state, the application is in operation or the like, and if the application is not in a switchable state, it is necessary to prohibit device switching. For example, switching to a printer is prohibited during data transfer of the scanner. If the switch is rejected, NAK is sent to the USB host 100 at the data stage of the vendor request.
(S616), and this process ends. NAK usually indicates that the request is not acceptable. The host-side device driver or application that has issued the switching request knows that switching is not possible by receiving the NAK, and performs a corresponding operation such as displaying a dialog.

In the above example, the function switching between the printer and the scanner has been described. However, the image server function (a function for storing image data printed on the MFP side in a hard disk or the like and reusing it). ), Fax function, etc.
It is possible to switch the function of FP. The frequency of using these functions for each user differs considerably. That is, it is not necessary to make all functions available at all times, and even if not all functions can be used at once, it does not cause much inconvenience to the user. By implementing the switching function, it is possible to use these functions from outside using an inexpensive USB controller without preparing endpoints for all of these device functions.

Further, when controlling the connection to the USB function by the above-mentioned vendor device request,
Debug and maintenance of one of the switching device functions
An embodiment having a Port (hereinafter referred to as “Debug Port”) function will be described below. FIG. 7 shows the state of U on the USB host 100 side.
3 shows a configuration of an SB driver layer. As shown in FIG. 7, the USB driver layer includes a Debug Port class driver 75 as one of the driver hierarchical structures.
A Debug Port MD 75m is provided between the rt class driver 75 and the USB bus class driver 71, and there is no other fundamental difference from FIG. FIG. 8 shows the configuration of the device driver 60 on the USB function 200 side. This corresponds to the USB driver on the USB host 100 side in FIG. 7, and as shown in FIG.
The SBDebug Port application 42 is provided as one of the devices controlled by the USB driver. Except for this point, the device driver on the USB function side in FIG. 8 is basically the same as the driver shown in FIG. The procedure of the connection control operation is the same as the procedure for connecting the scanner port to the device driver described above with reference to FIG. As described above, the host-side device driver has a function of transmitting a descriptor switching request vendor request, and the function side recognizes this and recognizes this, and has a descriptor switching function, a notification function for a device function using the driver, and a connection disconnection process. According to the control system, the host side and the function side can switch to a device having a different function for processing. In particular, when the function is an operation for debug maintenance, this enables the debug port to be used as a descriptor. Debug without exposing the function and without preparing an endpoint for the debug port.
A maintenance operation can be performed.

Next, the second connection control method will be described. The second connection control method is based on performing control transfer with a data stage for data transfer. By transmitting two vendor requests, connection with a specific function is made, and another port communication is enabled. In the function device driver on the host side, processing for communication is separately prepared as a specific function driver. An example of a class driver including the printer class driver 74 and the Debug Port class driver 75 shown in FIG. 7 will be described.
g A Port class driver 75 is provided. Here, the processing of the transmission / reception vendor request for Debug Port communication is further delegated to the printer class driver 74 which is a device driver inherent to the device. That is, Debug Po
The printer MD 74m is provided so that the request from the Debug Port MD 75m of the rt class driver 75 is handled by the printer class driver 74, and a debug transmission / reception request is issued from the printer MD 74m. The function side has a process for this vendor request as a device function.
Thus, the debug / maintenance operation can be performed without preparing an endpoint for the debug port without exposing the function of the debug port as a descriptor.

FIG. 4 shows a vendor device request used in the second connection control method. As shown in FIG. 4, the vendor device request is composed of five fields (standardized in the USB specification). The first bmRequestType indicates a vendor request, and the next bRequest identifies a specific request. In this example, bRequest of 0x72 is a request for debugging / maintenance data transmission (FIG. 4A), and bRequest of 0x73 is a request for data reception (FIG. 4B). The data length is specified by wLength, and the actual data is exchanged in the data stage of the request. Printer MD 74m is Debug Port MD
When a request is received from 75m, these two vendor requests are sent. The data returned as a result of the request and the like is transmitted from the printer MD74m to the Debug Port MD7.
5m passed. In addition, a process of delegating device status inquiry processing from the Debug Port MD 75m to the printer MD 74m is also performed.

The processing for the vendor request 0x72 / 0x73 is performed by the device driver E of the USB function 200 side.
This is performed by device request processing which is a part of the operation of the P0 manager 63 (see FIG. 8). This is performed according to the flowchart shown in FIG. 6 described above. In the processing flow shown in FIG. 6, the type of device request indicated by bmRequestType in the vendor device request (see FIG. 4), that is, the standard device request, the class device request, and the vendor device request are determined (S601, S607, S60).
9) The process is performed separately for each device request.
The device request of bmRequestType is not a standard device request or a class device request (S
If the request is determined to be a vendor request (S609), the type of the vendor request indicated in bRequest (see FIG. 4) is further identified (S61).
0, S617, S620).

As a result of the identification, the vendor request is 0x72,
That is, when the request is a request for transmission of debug / maintenance data (S617), the 0x72 vendor request has a data stage of reception (transmission from the host side) (S6).
18). In this process, data having a length according to the data length (wLength) in the vendor request (see FIG. 4A) is received. The received data is received by the USB debug port application 42 via the USB device I / F 61. or,
At the status stage, whether or not the reception was successful is returned to the host (S619). Vendor request is 0x73,
That is, when the request is for debugging / maintenance data reception (S620), the 0x73 vendor request has a data stage of transmission (reception from the host side) (S6).
21). According to the data length in the vendor request (see FIG. 4B), in the data stage, the USB device I / F 6
1 to transfer the data provided from the USB debug port application 42. After that, the host returns status information indicating that the transfer was successful (S622).
In this way, communication between the host-side debug port driver and the function-side debug port application can be performed by two vendor requests made via the printer class driver.

[0036]

(1) Effects corresponding to the first aspect of the invention Since the host has a device driver having a function of issuing a configuration switching vendor request, the functions of a plurality of devices (peripheral devices) are used. In this case, a communication path can be secured with a small number of endpoints without having the number of endpoints necessary for all of these functions. (2) Effects corresponding to the second aspect of the invention In addition to the effects of the above (1), by preparing a host-side device driver for each configuration,
It is possible to use a device driver having a simple configuration that does not require complicated control. (3) Effects corresponding to the third aspect of the invention When the control unit of the peripheral device receives a configuration switching vendor request, it performs bus reset or USB cable power-off processing, and sends a descriptor having the switched configuration to the host. To provide
By performing the operation of shifting to the operation state according to this configuration, the inventions of claims 1 and 2 can be easily implemented. (4) Effects Corresponding to Claim 4 In addition to the effect (3), the host-side device driver or application that has issued the switching request receives the NAK from the device side and knows that switching is not possible. Accordingly, it is possible to perform an operation corresponding to the display of a dialog or the like, and the convenience for the user is improved. (5) Effects corresponding to the invention of claim 5 In addition to the effects of the above (1) to (4), by setting one of the switchable configurations as a device configuration for debug maintenance communication, it can be used as a descriptor. The debug / maintenance operation can be performed without disclosing the function of the debug port and without preparing an endpoint for the debug port.

(6) Effects corresponding to the sixth aspect of the invention By having a device driver having a function of issuing a transmission and reception vendor request that enables a port communication by control transfer with a data stage, A communication path for using these functions can be secured with a small number of endpoints without having the number of endpoints necessary for all of the functions of a plurality of devices (peripheral devices). Also, the device driver on the host side using the function of issuing the transmission and reception vendor requests delegates the processing of this vendor request to the device driver of the device and assigns it to the device driver. By having it as a function, it becomes possible to operate the device without exposing the function of this port as a descriptor and preparing an endpoint for this port communication. (7) Effect corresponding to the invention of claim 7 In addition to the effect of the above (6), by using the port communication according to the present invention for communication for debug maintenance, the function of the debug port is not disclosed as a descriptor. In addition, the debug / maintenance operation can be performed without preparing an endpoint for the debug port. (8) Effects corresponding to the eighth aspect of the invention Peripheral devices are functions provided in a multifunction copier (for example, a machine having a combination of a copying function, a printer function, a facsimile function, a scanner function, an electronic filing function, etc.)
By configuring the peripheral device control system, the effects of the above (1) to (7) can be realized in the peripheral device control system including the multifunction copier as an element, thereby improving the performance of the system.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of a configuration of a peripheral device control system according to the present invention.

FIG. 2 shows a configuration example of a driver layer of a USB host.

FIG. 3 shows a vendor device request used for a “device descriptor switching request”.

FIG. 4 shows a vendor request used for transmission / reception by control transfer with a data stage.

FIG. 5: Device driver 1 of USB function
An example of the configuration is shown.

FIG. 6 shows a flowchart of a device request process which is a part of the operation of the EP0 manager.

FIG. 7 shows another configuration example of the driver layer of the USB host.

FIG. 8 shows another configuration example of the device driver of the USB function.

FIG. 9 shows a USB system topology.

FIG. 10 shows an example of a hierarchical structure of a Descriptor of a conventional peripheral device.

FIG. 11 shows another example of a hierarchical structure of a Descriptor of a conventional peripheral device.

[Explanation of symbols]

40: Device function, 41: USB print
App, 42… USBDebug Port app, 43… USBs
canner application 50 ... application, 60 ... USB driver (function side), 61 ... USB device I / F,
62: descriptor management unit, 63: EP0 manager, 70: USB driver (host side), 71
... USB bus class driver, 74 ... Printer class driver, 75 ... Debug Port class driver, 77 ... sc
anner class driver, 100 ... USB host,
200 ... USB function.

Claims (8)

[Claims] 1. A peripheral device control system for connecting a host and peripheral devices by a USB method, wherein the host has a device driver having a function of issuing a configuration switching vendor request. 2. The peripheral device control system according to claim 1, wherein the host has a device driver for each configuration. 3. The peripheral device control system according to claim 1, wherein the control unit on the peripheral device side having a function of receiving the configuration switching vendor request receives a configuration switching vendor request. A peripheral device control system that performs bus reset or USB cable power-off processing, provides a host with a switched descriptor having a predetermined configuration, and shifts to an operation state according to the configuration content. . 4. The peripheral device control system according to claim 3, wherein when a transition to an operation state according to a configuration switching request is not possible, the control unit on the peripheral device side returns a rejection response. A peripheral device control system, characterized in that: 5. The peripheral device control system according to claim 1, wherein one of the switched configurations is a device configuration for debug maintenance communication. . 6. A peripheral device control system for connecting a host and a peripheral device by a USB system, wherein the host has a function of issuing a transmission and reception vendor request for enabling port communication by control transfer with a data stage. A peripheral device control system comprising a driver. 7. The peripheral device control system according to claim 6, wherein said port communication is used for communication for debugging and maintenance. 8. The peripheral device control system according to claim 1, wherein said peripheral device has a function provided in a multifunction copying machine.