CN1123927A

CN1123927A - Circuit for exchanging floppy disk drives

Info

Publication number: CN1123927A
Application number: CN 94118034
Authority: CN
Inventors: 陈志贤
Original assignee: United Microelectronics Corp
Current assignee: United Microelectronics Corp
Priority date: 1994-12-03
Filing date: 1994-12-03
Publication date: 1996-06-05
Anticipated expiration: 2014-12-03
Also published as: CN1042676C

Abstract

The circuit device for exchanging floppy drives A with B in computer comprises a controller and an exchange circuit controlled by the said controller, and features no need of modifying structure and no limitation from software such as operating system. It may be also arranged in the control chip of floppy drive.

Description

The circuit arrangement that floppy disk is exchanged

The present invention is relevant for the disc driver circuit arrangement in a kind of computer, particularly relevant for a kind of circuit arrangement that makes two floppy disks exchanges of computer.

In recent years, because computer raising constantly on performance, and price constantly descends, and makes that the scope of computer applications is very general.

In the computer system now, floppy disk is a kind of storage device of indispensability.Generally speaking, PC can be installed two floppy disks, respectively called after A: floppy disk and B: floppy disk.Wherein, A: floppy disk is very important in computer system, because common A: floppy disk has the function as the start floppy disk.

On using, because A: the importance of floppy disk, so with A: floppy disk and B: the floppy disk exchange is used, and is necessary in some cases.Now lifting following several situation is example:

(1) can be divided into two kinds on the physical size of floppy disk: one is 1.2MB formula floppy disk, and floppy disk that this floppy disk adopts is of a size of 51/4 inch; Another is a 1.44MB formula floppy disk, and its floppy disk that adopts is of a size of 31/2 inch.Because the floppy disk size of above-mentioned amphitypy is not inconsistent, therefore, generally speaking, above-mentioned amphitypy floppy disk can not be compatible.So when two floppy disks of computer are installed, can select each one of 1.2MB floppy disk and 1.44MB floppy disk, name wherein one be A: floppy disk.When the user under must situation, if called after A by floppy disk start: floppy disk and existing start floppy disk and when incompatible, just existing two floppy disks must be done exchange.

(2) in some package software, some situation must be done exchange with two floppy disks that have different size now.As installation, access data etc.

(3) A in the former computer system: the floppy disk fault, wish before maintenance is finished temporarily with B: floppy disk is regarded A: floppy disk.

Above-mentioned some situations only are the PC user parts in the chance situation often, in fact should have more situation floppy disk must be done exchange.

The most direct solution to the problems described above is promptly taken casing apart, will connect the line refitting of floppy disk.But this method has its shortcoming, not only takes casing apart, and the refitting line needs the suitable hardware professional knowledge of tool, and non-general user can implement arbitrarily; And sometimes be subject to wire length and joint kind, reclosing easily; Promptly allow to reclosing, to be used finishing wanted reinstatement, very trouble.And it is, infeasible especially and tool is dangerous for the line of must when package software is carried out, resetting.Be so though solution can solve afore-mentioned (1) and situation (3), but when implementing and be not easy, moreover powerless especially for situation (2).

Therefore, solution is promptly arisen at the historic moment more easily.Up-to-date method promptly is in the basic input/output (BIOS) in PC, to provide a software simulation function.The user can be provided in the setting program (setup program) of personal computer system this moment the option of similar " exchange A:/B: " (Swap A:/B :), after the user selects to start (Enable) to this option, basic input/output (BIOS) can be in interrupt service routine (Int-errupt Service Routine, ISR) this exchange function of middle software simulation.Though the method proportion load line is convenient, and the function that can provide package software to exchange; But the operating system of not calling out the BIOS interrupt service routine for some is still invalid.For instance, operating system OS/2 promptly is an example wherein.

Fundamental purpose of the present invention provides a kind of circuit arrangement that floppy disk is exchanged, and is different from the solution of knowing software simulation in the technology, practically floppy disk is exchanged.

Another object of the present invention provides a kind of circuit arrangement, for operating system of not calling out the BIOS interrupt service routine or package software, solves the problem that it exchanges disk.

The invention provides a kind of circuit arrangement that floppy disk is exchanged, be positioned at the floppy disk bus, this circuit arrangement comprises: a control device, in order to produce a control signal; An and floppy disk interchange circuit, its input end is that bus the 10th from the floppy disk controller is to the 16th data line, its output terminal is to deliver to the bus the 10th of floppy disk joint to the 16th data line, the control signal that above-mentioned control device produces is controlled the function of this floppy disk interchange circuit, when true value, expression is carried out floppy disk and is exchanged function; When falsity, expression is not carried out floppy disk and is exchanged function;

When control signal was the logic falsity, to the 16th data line, the bus the 10th of output of directly delivering to the same No. number was to the 16th data line with the bus the 10th of input for this floppy disk interchange circuit;

When control signal is logic true value, bus the 16th and the 10th data line that this floppy disk interchange circuit exchanges to output with the bus the 10th and the data of the 16th data line of input, in like manner, bus the 12nd and the 14th data line are also done exchanges data.

Brief Description Of Drawings

Fig. 1 is a floppy disk interchange circuit schematic representation of apparatus of the present invention.

Fig. 2 is the floppy disk interchange circuit figure of the embodiment of the invention.

Embodiment

In general, personal computer system is controlled this two floppy disk A by an interface with floppy disk driver card 1 (please refer to Fig. 1): with B:.And interface with floppy disk driver card 1 with signal D1～D34 via joint J ₀Be connected to a line (not shown); The other end of line has two joints, with joint J ₁The floppy disk that connects is A: floppy disk, and with joint J ₂The floppy disk that connects is B: floppy disk.By the right of Fig. 1 as can be known, joint J ₁With joint J ₂The difference of the signal that is picked out is to be positioned at joint J ₁With joint J ₂Between line, to signal D16 line, passed through a turnover at signal D10.Therefore, the A in the PC: floppy disk and B: the position of floppy disk promptly is to utilize signal D10 to be distinguished to the forward of signal D16 is reverse.

In theory, the turnover state in the above-mentioned winding displacement is to have reversible characteristic; That is, at B: floppy disk (joint J ₂) and A: floppy disk (joint J ₁) (be joint J before ₂Before) do a turnover, can be with joint J ₂In (D10, D12, D14, D16) burst change into (D16, D14, D12, D10) burst, i.e. A: the burst of floppy disk; Simultaneously, joint J ₁Also be converted to B: the burst of floppy disk.The method has the function that floppy disk exchanges: A: floppy disk becomes B: floppy disk, B: floppy disk becomes A: floppy disk.

Above-mentioned turning device with a floppy disk interchange circuit 3 (please refer to Fig. 1 left side), places among the floppy disk control chip 2 during enforcement, is an integrated circuit.This kind mounting means be known to the most effective application mode, but this floppy disk interchange circuit 3 is if place interface with floppy disk driver card 1 or joint J ₀On the winding displacement of output, be a discrete circuit, even be an independent integrated circuit, same essence spirit according to the invention.Whether this floppy disk interchange circuit effect, is that the state (control signal CO) according to control device 4 decides.Control device 4 can be a register, " exchange A:/B: " control in the function choosing-item by setting program; Also can be a mechanical switch, through input/output end port (I/O Port) directly by hardware or software control.

Please refer to Fig. 2, this is the detailed circuit of floppy disk interchange circuit.Four MUX (selection input (the S1～S4) control of M1～M4) by control signal CO.When control signal CO was logical zero, ((O1～(A1～A4), this moment, signal sequence was (E10, E12, E14, E16) to the output signal of M1～M4) to MUX, the state of promptly not transferring O4) to be first input signal; When control signal CO was logical one, (O1～(B1～B4), this moment, signal sequence was (E16, E14, E12, E10) to output signal, the state of promptly transferring O4) to be second input signal.

The present invention utilizes a circuit arrangement, and with A in the computer: floppy disk and B: floppy disk is done an exchange.The advantage of this circuit arrangement is and needn't restructures, and also can solve on the other hand and know the restriction that technology is subjected to softwares such as operating system.And this floppy disk interchange circuit device can directly place in the floppy disk control chip on the implementation, and is for the application on the industry, very convenient.

Though the present invention discloses as above with a preferred embodiment; right its is not in order to qualification the present invention, any those skilled in the art, without departing from the spirit and scope of the present invention; when the change that can do a little and retouching, so protection scope of the present invention limits when looking accompanying Claim.

Claims

1, a kind of circuit arrangement that floppy disk is exchanged is positioned at the floppy disk bus, comprises:

One control device is in order to produce a control signal; And

One floppy disk interchange circuit, its input end is that bus the 10th from the floppy disk controller is to the 16th data line, its output terminal is to deliver to the bus the 10th of floppy disk joint to the 16th data line, the described control signal that described control device produces is controlled the function of described floppy disk interchange circuit, when true value, expression is carried out floppy disk and is exchanged function; When falsity, expression is not carried out floppy disk and is exchanged function;

When described control signal was the logic falsity, to the 16th data line, the bus the 10th of output of directly delivering to the same No. number was to the 16th data line with the bus the 10th of input for described floppy disk interchange circuit;

When described control signal is logic true value, bus the 16th and the 10th data line that described floppy disk interchange circuit exchanges to output with the bus the 10th and the data of the 16th data line of input, in like manner, bus the 12nd and the 14th data line are also done exchanges data.

2, in the floppy disk interchange circuit device as claimed in claim 1, described floppy disk interchange circuit comprises four MUX.

3, in the floppy disk interchange circuit device as claimed in claim 1, described floppy disk interchange circuit is an integrated circuit, places the control chip of floppy disk.

4, in the floppy disk interchange circuit device as claimed in claim 1, described floppy disk interchange circuit places on the interface with floppy disk driver card.

5, in the floppy disk interchange circuit device as claimed in claim 1, described control device is a register.

6, in the floppy disk interchange circuit device as claimed in claim 1, described control device is a mechanical switch.