KR950004209B1 - Fdd apparatus - Google Patents

Abstract

The apparatus provides a software tool to change a hard disk number installed in computer system without changing the hardware configuration. The apparatus comprises; a floppy disk driver outputting the motor enable signal and driver selection signal; an address decoder(25) outputting the ADDR signal with a CPU address input or OR gate (OR1) taking input IOW signal and ADDR signal; a D flip flop(24) to correspond to the CPU data; several tri state buffers(BF1 or BF8); several open collector type buffers(BUF1-BUF4) to transmit the tri state buffer output to the floppy disk drivers(22,23).

Description

Floppy Disk Driver Switching Device

1 is a block diagram showing a conventional floppy disk driver interface.

2 is a block diagram showing a floppy disk driver switching device of the present invention

3 is a flowchart showing the operating principle of the software of the present invention.

* Explanation of symbols for the main parts of the drawings

11,21: floppy disk controller 12,22: the first floppy disk driver

13,23: second floppy disk driver 24: D-flip flop

25 address decoder 31 set-up software

32: Post Software

The present invention relates to an interface between a floppy disk driver and a floppy disk controller of a computer system capable of supporting two or more floppy disks. The present invention relates to a floppy disk driver switching device in which designation numbers of a plurality of floppy disk drivers can be changed using software without changing hardware.

In general, the designation number of the floppy disk driver is determined by the designation number of the driver selection signal and the motor enable signal, which are the outputs of the floppy disk controller. Therefore, if the connection between the floppy disk driver and the floppy disk controller output is adjusted, You can specify the number of the floppy disk driver.

However, in the case where the computer system can support two floppy disk drivers, the conventional floppy disk driver switching device has a floppy disk because the interface between the floppy disk driver and the floppy disk controller is fixed in hardware as shown in FIG. In order to change the designation number of the driver, there is a difficulty in disassembling the system and changing the driver select jumper in the floppy disk driver or replacing the floppy disk driver interface cable.

That is, the first floppy disk driver 12 selected by the driver selection signal DS0 and the motor enable signal ME0, which are outputs of the floppy disk controller 11 shown in FIG. 1, is a 3.5-inch (Inch) disk driver, and the DS1 signal. If the second floppy disk driver 13 selected by the and ME1 signals is a 5.25 inch disk driver, it is not supported to use the 5.25 inch disk driver as the first floppy disk driver, and the output of the floppy disk controller 11 The first floppy disk driver 12 selected by the driver search signal DS0 and the motor enable signal ME0 is a 5.25 inch floppy disk driver, and the second floppy disk driver 13 selected by the DS1 signal and the NIE1 signal is a 3.5 inch floppy disk. Driver, use the 3.5-inch disk driver as the first floppy disk driver. If you do, there will be problems that are not supported.

Therefore, in the present invention, by configuring a floppy disk driver switching device to control the interface between the floppy disk controller and the floppy disk driver by a software program, the user can convert the specified number of the floppy disk driver as needed, Its purpose is to eliminate the problems previously encountered with floppy disk driver interfaces.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

FIG. 2 is a block diagram showing a floppy disk driver switching device of the present invention. When power is initially turned on, a -PWR (Power On Reset) signal transitions to a logic low level for a predetermined period of time. -Clears the DO signal output from the flip-flop 24 to the logic low level, thereby enabling the tri-state buffers BFl and BF2 to enable the floppy disk. The first floppy disk driver 22 is designated as the first floppy disk driver by passing the output DS0 and NIE0 signals of the controller 21 to the DSS0 and NlES0 signals, which are outputs of the Open Collector Type Buffer BUFl and BUF2. To transfer the output DS1 and ME1 signals of the enable-seeker floppy disk controller 21 to the DSS1 and MES1 signals of the open-collect type buffers BUF3 and BUF4 by passing the tri-state buffers BF7 and BF8 to the second floppy disk driver 23. To the second floppy Specify a big driver.

A PWR signal is maintained at a logic low state for a predetermined time and then transitions to a logic high state, which is an output of an address decoder 25 that inputs a CPU address (Central Processing Unit Address). When the output of the OR gate OR1 generates the logic low state pulse signal by the ADDR signal and the -IOW signal, which is a CPU command, the output of the D-flip flop 24 depends on the logic state of the CPU data. The logic states of the DO and -DO signals are changed, and the connection state between the floppy disk controller 21 and the floppy disk drivers 22 and 23 is determined accordingly. (At this time, the CPU address, -IOW signal, and CPU data are signals output from the CPU by software for adjusting the interface between the floppy disk controller and the floppy disk driver. The software accepts the information input by the user and processes it. do.)

When the CPU data has a logic low state due to an external input, the output DO and -DO signals of the D-flop flop 24 transition to the logic low and logic high states, respectively, to clear the tri-state buffers BFl, BF2, BF7, and BF8. Since it is enabled, the DS0 and ME0 signals are transmitted to the DSS0 and MES0 signals to designate the first floppy disk driver 22 as the first floppy disk driver, and the DS1 and ME1 signals are transmitted to the DSS1 and MES1 signals so that the second floppy disk is transmitted. The driver 23 is designated as the second floppy disk driver.

On the other hand, when the CPU data has a logic high state due to an external input, the output DO and -DO signals of the D-flop flop 24 transition to the logic high and logic low states, respectively, so that the tri-state buffers BF3, BF4 and BF5 Since BF6 is enabled, the DS0 and ME0 signals are transmitted to the DSS1 and MES1 signals to designate the second floppy disk driver 23 as the first floppy disk driver, and the DS1 and ME1 signals are transmitted to the DSS0 and MES0 signals. Floppy disk driver 22 is designated as the second floppy disk driver.

As described above, the user can input the appropriate signal from the outside to adjust the CPU data so that the designated numbers of the floppy disk drivers can be switched as necessary.

FIG. 3 is a flowchart illustrating the operation principle of the software of the present invention. After determining whether to perform Set-Up software when the power is turned on, FIG. Proceed to the set-up software 31 by asking the user for the status to be programmed (Status) to receive the status, and storing the entered status in the non-volatile random access memory (Non Volatlle Random Access Memory). Once the entered status is stored in the nonvolatile RAM, it is determined whether to perform the setup software again. Then, the status stored in the nonvolatile RAM is read and the D-flip flop of FIG. Program to determine the designation numbers of the floppy disk drivers as described in Figure 2. After testing the opponent, the process of booting an OS (Operating System) is performed.

As described above, when the interface between the floppy disk controller and the floppy disk driver is adjusted according to the method of the present invention described with reference to FIGS. 2 and 3, the user can use the software as needed without having to change the hardware of the assigned number of floc disks. By doing so, you can easily determine the effect.

Claims (2)

In a computer system supporting two or more floppy disks, the floppy disk controller 21 which outputs a driver selection signal and a motor enable signal to determine the designation number of the floppy disk drivers, and the CPU by the user input state. The address decoder 25 for outputting the -ADDR signal by inputting the CPU address outputted from the < Desc / Clms Page number 5 >, the oragate ORl for inputting the -ADDR signal and the -IOW signal, which is the CPU instruction, OR-) and D-flip flop 24, which is controlled by the -PWR signal that is the output of the power supply and transfers the CPU data generated by the state input from the user to DO and -DO, and the floppy. The driver selection signal and the motor enable signal, which are outputs of the disk controller 21, are selectively selected by the floppy disk drivers 22 and 23 according to the output of the D-flip flop 24 described above. Several tri-state buffers BF1 to BF8 for connection to the memory, and several open collects for transmitting signals transmitted from the tri-state buffers BF1 to BF8 to the floppy disk drivers 22 and 23. Floppy disk driver switching comprising a type buffer BUF1 to l3UF4 and floppy disk drivers 22 and 23 whose designation numbers are determined according to signals transmitted from the open collect type buffers BUF1 to BUF4. Device. 2. The floppy disk driver switching device according to claim 1, wherein the state for controlling the D-flop flop (24) is stored in the nonvolatile RAM and the D-flop flop is controlled using the same.