CN203799373U

CN203799373U - Difunctional USB equipment

Info

Publication number: CN203799373U
Application number: CN201420093575.8U
Authority: CN
Inventors: 席卫平
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-03-04
Filing date: 2014-03-04
Publication date: 2014-08-27
Anticipated expiration: 2024-03-04

Abstract

The utility model provides difunctional USB equipment which comprises a ten-core signal socket, a microprocessor, a USB interface and an induction pin switch circuit. Programs for achieving two functions are written in the microprocessor, the USB interface is a known electrical standard meeting a USB interface protocol, and the ten-core signal socket is used for redefining an unoccupied pin of a ten-core socket for a known ISP downloading device to be a signal pin needed by another function equipment. The induction signal pin switch is a switch, and is switched between a high level and a low level. The programs in the microprocessor detect the change of the induction pin switch, the work mode is changed, and the equipment is switched into another function from one function. Only one USB interface resource is occupied by the difunctional interface equipment, the ten-core socket can achieve the two functions of the USB equipment, and the functions can be switched only by stirring the switch. The equipment is few in occupied resource, easy and convenient to operate, low in production cost, wide in application prospect and suitable for being popularized.

Description

A kind of difunctional USB device

Technical field

The utility model relates to infotech research and development fields, particularly single-chip microcomputer (microprocessor), embedded development and application.

Background technology

In today of large scale integrated circuit technology develop rapidly, the product relevant to electronic information technology generally adopted single-chip microcomputer or embedded technology; Associated curricula has also entered in the scientific and technological activities of universities and even middle and primary schools.

Because integrated level is high, that single-chip microcomputer or embedded chip have all carried on sheet is jumbo, can be repeatedly information also can not be lost after erasable, power down repeatedly storer.The in-built program code carrying for single-chip microcomputer or embedded chip autonomous operation of sort memory, is known as " firmware ".

It is first to use on computers high level computer Programming Languages, coding that people will write firmware as the step 1 of single-chip microcomputer or embedded chip; Then through compiling system, higher level lanquage is converted to single-chip microcomputer or embedded discernible machine code, finally by a kind of instrument: downloader, is downloaded to the storer in chip.

At present, downloader is connected and can has multiple implementation method with goal systems, and commonplace is to adopt known 10 core cables, connects downloader and goal systems, and Figure of description 2 has provided its pin definitions.Downloader and computer also can be by multiple connected modes, serial ports, parallel port etc.Day by day universal along with notebook computer, it is more conventional that the downloader of USB interface also becomes.

On the other hand, during single-chip microcomputer or process of embedded system exploitation and application, can often use serial ports, but due to the restriction of notebook computer self structure, often cancel 9 needle sockets of serial port communicating protocol requirement.But this does not mean that serial ports is cancelled, operating system is still supported serial communication as Windows, solution is by usb protocol simulative serial port communications protocol, adopts technological means to pass through a USB bridging device simulative serial port communications protocol, allows operating system identify and generate a virtual serial port.

By above analysis, we are not difficult to find, USB downloader and USB/ serial converter have become not opening of single-chip microcomputer and embedded system development, study or scarce equipment.

Problem is, two kinds of equipment use simultaneously, on the one hand the hardware resource of computer taken morely, uses USB expansion equipment to mean fund input.On the other hand, user's goal systems need provide two interface sockets, and one connects downloader, and one connects serial ports, is also a kind of waste.

Utility model content

Take the too much problem of computer USB interface resource for solving, the utility model provide a kind of take a USB interface, 10 core sockets but possess two kinds of functions of the equipments solution easy and simple to handle.

The utility model solves the technical scheme that its technical matters adopts: adopt so a kind of circuit design, taking a microprocessor as core, it is input as the standard interface hardware circuit that meets known USB communications protocol electrical code, it is output as 10 needle sockets that known ISP downloader is used, and connects 10 core cables to target microcontroller system board.The program software of resident two kinds of functions in described microprocessor.Described standard USB interface completes the function that allows Windows operating system be identified as the external unit of plug and play; But now which kind of equipment computer can't be confirmed to be.An I/O pin of described microprocessor, as perception pin, connects a toggle switch, connect+5V of the utmost point high level of toggle switch, and a utmost point meets 0V.User at any time toggle switch selects the function oneself needing.The level of the resident software real-time query perception pin in described microprocessor changes, once find to change, program redirect immediately enters the program part operation of relevant device, reply the inquiry that on host computer, Windows operating system is sent, allow computer identify the kind of this equipment, and demonstrate this equipment in hardware management module.Described known ISP retains former definition with most pins of 10 core sockets, is from being newly defined as the send and receive pin for serial ports by the idle pin of former ground connection 4 and 6.

By implementing above technical scheme, there is following technique effect: only take a USB interface, user has just accessed two USB device, only need simply stir a switch and can complete function switching.Ownership goal circuit board also can save former serial communication socket in the time of design, and serial ports and downloader are merged into 10 core sockets.

Brief description of the drawings

Figure mono-: be the utility model hardware principle block diagram

Figure bis-: be the utility model 10 core socket definition figure

Figure tri-: be Single Chip Microcomputer (SCM) program process flow diagram of the present utility model

Figure tetra-: be the circuit diagram of the utility model embodiment

Embodiment

In order better to understand the technical solution of the utility model, describe below in conjunction with accompanying drawing 1, Fig. 2, Fig. 3 and Fig. 4 the embodiment that the utility model provides in detail.

The utility model embodiment provides a kind of to take a USB interface, has USB downloader and USB concurrently and turns the bifunctional USB device of serial ports.Bifunctional USB device, as the circuit diagram that Fig. 4 is this utility model embodiment, comprising: 10 core socket 1-1 for lower carrier communication and serial communication interface, microprocessor 2-1, standard USB interface circuit part 3-1, perception pin circuitry part 4-1, current function indicating section 5-1.In the present embodiment, described microprocessor 2-1 is a slice Atmega8 single-chip microcomputer, inner with resident firmware program, realize two functions: download assembler code to the function of target microcontroller and USB interface converted to the function of a virtual serial port by USB interface.Described standard USB interface circuit part 3-1 is the hardware circuit of following USB communications protocol electrical code, and when this interface inserts after the computer of Windows operating system, operating system can find that there is the equipment access of plug and play; So start the communication program that sets USB device.Microprocessor 2-1 circulates a notice of self functional mode of living according to the current state of perception pin circuitry 4-1, or is USB downloader, or is serial converter.Current function indicating section 5-1 lights the pilot lamp of different colours according to the difference of function, to indicate current work energy pattern of living in.

The utility model embodiment is when in USB downloader work energy pattern, and 1,5,7,9 pins of interface socket 1-1 use as pin MOSI, SS, SCK, the MISO of known ISP downloader 1-2, complete downloading to target microcontroller of task.When turn serial ports work energy pattern in USB, RXD (receipts) and TXD (sending out) function that 4,6 pins of interface socket 1-1 are taken on respectively serial ports 2-2, realize serial communication.

User can stir the switch of perception pin circuitry 4-1 as required at any time, and the utility model embodiment is under the state of working on power, and microprocessor 2-1 is the current state of inquiry perception pin circuitry 4-1 constantly, once find to change transformation working pattern immediately.

The difunctional USB device of one above the utility model embodiment being provided is described in detail, for one of ordinary skill in the art, according to the thought of the utility model embodiment, all will change in specific embodiments and applications, in sum, this description should not be construed as restriction of the present utility model.All within spirit of the present utility model and principle, any amendment of doing, be equal to replacement etc., within all should being included in protection domain of the present utility model.

Claims

1. a difunctional USB device, it is characterized in that, comprising: write the microprocessor of two kinds of function programs, meet the interface of known USB communications protocol electrical code, the 10 core sockets that comprise two kinds of function communications protocol pins, the switch that can the perception outside level of described microprocessor changes.

2. difunctional USB device as claimed in claim 1, is characterized in that, on the basis of former known ISP downloader 10 core socket pin definitions, uses idle pin assignments to another function.

3. difunctional USB device as claimed in claim 1 or 2, is characterized in that described microprocessor is the single-chip microcomputer of any model.