Mouse interface converter for connecting mouse to computers with different types of connecting ports

• US 6,247,075 B1
• Filed: 10/14/1998
• Issued: 06/12/2001
• Est. Priority Date: 06/24/1998
• Status: Expired due to Fees

• Current Assignee: Primax Electronics Limited
• Original Assignee: Primax Electronics Limited
• Inventors: Wang, Han-Che, Chou, Wen-Pin, Shih, Tzu-Chiang
• Primary Examiner(s): Lee, Thomas
• Assistant Examiner(s): SCHUSTER, KATHARINA W
• Application Number:
  US09/172,336
• Time in Patent Office: 972 Days
• Field of Search: 710/63, 710/127, 710/62, 710/129, 710/5, 710/72, 710/64, 178/18, 713/300, 345/157, 361/601
• US Class Current: 710/63
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device

Abstract

A mouse interface converter is provided, which allows a mouse to be connectable to a computer system, such as a personal computer (PC), installed with either an RS-232 serial port or a PS/2 port. This mouse interface converter allows the mouse to be connected directly to PS/2 port and via an adapter to RS-232 serial port. The mouse interface converter includes a mode-detection circuit for detecting which type of port the mouse is currently being connected. The mode-detection circuit can generate a mode-indicating signal indicative of the type of the currently connected port, which is then used to set a control circuit to convert the mouse data to the corresponding format. The mouse interface converter further includes a driving circuit that allows the mouse to be more compatible with various signals of either the PS/2 port or the RS-232 serial port. This feature allows the mouse to be considerably reduced in power consumption that allows the mouse to be suitable for use on notebook computers.

Claims

1. In a mouse, a mode-detection circuit capable of detecting whether the mouse is currently being connected to an RS-232 serial port or a PS/2 port, the mouse having a control circuit capable of converting mouse data into either RS-232 format or PS/2 format depending on the logic state at a mode port thereof;

the mode-detection circuit comprising;

a first resistor having a first end connected to a system voltage and a second end connected to a common node;

a second resistor which is greater in resistance than the first resistor, and which has a first end connected to the common node connected to the first resistor and a second end connected to a signal line;

the signal line being connected to an NC signal line when the mouse is coupled to PS/2 port and to a T×

D signal line when coupled to RS-232 serial port; and

a third resistor which is equal in resistance to the first resistor, and which has a first end connected to the common node connected to the first resistor and the second resistor and a second end connected to the mode port of the control circuit;

wherein when the mouse is coupled to PS/2 port, the mode-indicating signal obtained from the common node is at high-voltage logic state, causing the control circuit to convert the mouse data into PS/2 format; and

when the mouse is coupled to RS-232 serial port, the mode-indicating signal obtained from the common node is at low-voltage logic state, causing the control circuit to convert the mouse data into RS-232 format.

12. The mouse interface converter of claim 1, further comprising:

a ground port which, when the mouse is connected to PS/2 port, is connected to the GND signal line of the PS/2 port; and

when the mouse is connected to RS-232 serial port, is connected to the GND signal line of the RS-232 serial port.

2. In a mouse, a driving circuit capable of driving the mouse when the mouse is currently being connected to an RS-232 serial port;

the mouse having a control circuit having a DATA port for outputting the mouse data to the RS-232 serial port;

the driving circuit comprising;

a pull-up transistor having a control end connected to the DATA port of the control circuit, a first end connected to a system voltage, and a second end connected to a common node;

the pull-up transistor being switched into conducting state between the first and second end when the control end thereof receives a high-voltage logic state in the output data from the DATA port of the control circuit;

a pull-down transistor having a control end connected to the second end of the pull-up transistor, a first end connected to an R×

D/NC port, and a second end connected to a T×

D/NC port;

when the mouse is coupled to RS-232 serial port, the T×

D/NC port being connected to the T×

D signal line of the RS-232 serial port;

a resistor having a first end connected to the common node and a second end connected to the second end of the pull-down transistor; and

a diode having a positive end connected to the common node and a negative end connected to the first end of the pull-down transistor;

wherein when a high-voltage logic state appears in the output data from the DA-TA port of the control circuit, it causes the pull-up transistor to be switched into non-conducting state, thereby pulling the R×

D signal line of the RS-232 serial port to high-voltage logic state via the diode and the R×

D/NC port; and

when a low-voltage logic state appears in the output data from the DATA port of the control circuit, it causes the pull-down transistor to be switched into conducting state, thereby pulling down the voltage state of the R×

D signal line of the RS-232 serial port to equal to the voltage state of the T×

D signal line.

3. The driving circuit of claim 2, wherein the pull-up transistor is an NPN BJT whose base is connected to receive the output data from the DATA port of the control circuit, whose collector is connected to the system voltage, and whose emitter is connected to the common node.

4. The driving circuit of claim 2, wherein the pull-down transistor is a PNP BJT whose base is connected to the common node, whose emitter is connected to the R×

D/NC port, and whose collector is connected to the T×

D/NC port.

13. The mouse interface converter of claim 2, further comprising:

a Zener diode having a negative end connected to the system voltage input port of the mouse and a positive end connected to the ground, for maintaining the system voltage input port at a preset voltage level to drive the mouse.

5. In a mouse, an adaptor for the mouse, when connected to an RS-232 serial port, to fetch working current from the RS-232 serial port;

the adaptor comprising;

a first diode having a positive end connected to the DTR signal line of the RS-232 serial port and a negative end connected to the system voltage input port of the mouse;

a second diode having a positive end connected to the RTS signal line of the RS-232 serial port and a negative end connected to the system voltage input port of the mouse; and

a resistor having a first end connected to the RTS signal line of the RS-232 serial port and a second end connected to the clock signal input port of the mouse.

6. The adaptor of claim 5, further comprising:

a Zener diode having a negative end connected to the system voltage input port of the mouse and a positive end connected to the ground, for maintaining the system voltage input port at a preset voltage level to drive the mouse.

7. A mouse interface converter for use on a mouse to allow the mouse to be connectable to a PC with either a serial port or a PS/2 port, the mouse having a control circuit capable of converting mouse data into either RS-232 format or PS/2 format depending on the logic state at a mode port thereof;

the mouse interface converter comprising;

a mode detection circuit for detecting the voltage status of the connected port to thereby generate a mode-indicating signal indicative of whether the mouse is currently being connected to RS-232 serial port or PS/2 port;

the mode-indicating signal being input to the mode port of the control circuit;

a driving circuit having an R×

D/NC port and a T×

D/NC port respectively connected to, when the mouse is connected to RS-232 serial port, the R×

D signal line and T×

D signal line of the RS-232 serial port, which is capable of pulling the R×

D signal line of the RS-232 serial port to high-voltage logic state when a high-voltage logic state appears in the output data from the DATA port of the control circuit, and pulling down the voltage state of the R×

D signal line of the RS-232 serial port to equal to the voltage state of the T×

D signal line when a low-voltage logic state appears in the output data from the DATA port of the control circuit;

an adaptor for coupling the control circuit, the mode-detection circuit, and the driving circuit to the RS-232 serial port in such a manner that the R×

D/NC port of the driving circuit is connected directly to the R×

D signal line of the RS-232 serial port, the T×

D/NC port of the driving circuit is connected directly to the T×

D signal line of the RS-232 serial port, and the system voltage input port takes on the voltage state at the DTR signal line and RTS signal line of the RS-232 serial port;

wherein the adaptor comprises;

a first diode having a positive end connected to the DTR signal line of the RS232 serial port and a negative end connected to the system voltage input port of the mouse;

a second diode having a positive end connected to the RTS signal line of the RS232 serial port and a negative end connected to the system voltage input port of the mouse; and

a resistor having a first end connected to the RTS signal line of the RS-232 serial port and a second end connected to the clock signal input port of the mouse;

when the mouse is connected to RS/2 port, the DATA port of the control circuit is directly connected to the data input port of the PS/2 port, the system voltage input port of the mouse is connected to a voltage signal line of the PS/2 port, the R×

D/NC port of the driving circuit is connected to a first NC signal line of the PS/2 port, and the T×

D/NC port of the driving circuit is connected a second NC signal lne of the PS/2 port; and

when the mouse is connected via the adaptor to RS-232 serial port, the clock input port of the mouse is connected to the RTS signal line of the RS-232 serial port;

the system voltage input port of the mouse is connected to the DTR signal line and the RTS signal line of the RS-232 serial port;

the R×

D/NC port of the driving circuit is connected to the R×

D signal line of the RS-232 serial port; and

the T×

D/NC port of the driving circuit is connected to the T×

D signal line of the RS-232 serial port.

8. The mouse interface converter of claim 7, wherein the mode-detection circuit comprises:

a first resistor having a first end connected to a system voltage and a second end connected to a common node;

a second resistor which is greater in resistance than the first resistor, and which has a first end connected to the common node connected to the first resistor and a second end connected to a signal line;

the signal line being connected to an NC signal line when the mouse is coupled to PS/2 port and to a T×

D signal line when coupled to RS-232 serial port; and

a third resistor which is equal in resistance to the first resistor, and which has a first end connected to the common node connected to the first resistor and the second resistor and a second end connected to the mode port of the control circuit.

9. The mouse interface converter of claim 7, wherein the driving circuit comprises:

a pull-up transistor having a control end connected to the DATA port of the control circuit, a first end connected to a system voltage, and a second end connected to a common node;

the pull-up transistor being switched into conducting state between the first and second end when the control end thereof receives a high-voltage logic state in the output data from the DATA port of the control circuit;

a pull-down transistor having a control end connected to the second end of the pull-up transistor, a first end connected to an R×

D/NC port, and a second end connected to a T×

D/NC port;

when the mouse is coupled to RS-232 serial port, the T×

D/NC port being connected to the T×

D signal line of the RS-232 serial port;

a resistor having a first end connected to the common node and a second end connected to the second end of the pull-down transistor; and

a diode having a positive end connected to the common node and a negative end connected to the first end of the pull-down transistor.

10. The mouse interface converter of claim 7, wherein the adapter further comprises:

a Zener diode having a negative end connected to the system voltage input port of the mouse and a positive end connected to the ground, for maintaining the system voltage input port at a preset voltage level to drive the mouse.

11. A mouse interface converter for use on a mouse to allow the mouse to be connectable to a PC with either a serial port or a PS/2 port, the mouse having a control circuit capable of converting mouse data into either RS-232 format or PS/2 format depending on the logic state at a mode port thereof;

the mouse interface converter comprising;

a mode-detection circuit for detecting the voltage status of the connected port to thereby generate a mode-indicating signal indicative of whether the mouse is currently being connected to RS-232 serial port or PS/2 port;

the mode-indicating signal being input to the mode port of the control circuit;

the mode-detection circuit including;

a driving circuit having an R×

D/NC port and a T×

D/NC port respectively connected to, when the mouse is connected to RS-232 serial port, the R×

D signal line and T×

D signal line of the RS-232 serial port, which is capable of pulling the R×

D signal line of the RS-232 serial port to high-voltage logic state when a high-voltage logic state appears in the output data from the DATA port of the control circuit, and pulling down the voltage state of the R×

D signal line of the RS-232 serial port to equal to the voltage state of the T×

D signal line when a low-voltage logic state appears in the output data from the DATA port of the control circuit; and

an adaptor for coupling the control circuit, the mode-detection circuit, and the driving circuit to the RS-232 serial port in such a manner that the R×

D/NC port of the driving circuit is connected directly to the R×

D signal line of the RS-232 serial port, the T×

D/NC port of the driving circuit is connected directly to the T×

D signal line of the RS-232 serial port, and the system voltage input port takes on the voltage state at the DTR signal line and RTS signal line of the RS-232 serial port;

wherein

the mode-detection circuit includes;

a first resistor having a first end connected to a system voltage and a second end connected to a common node;

a second resistor which is greater in resistance than the first resistor, and which has a first end connected to the common node connected to the first resistor and a second end connected to a signal line;

the signal line being connected to an NC signal line when the mouse is coupled to PS/2 port and to a T×

D signal line when coupled to RS-232 serial port; and

a third resistor which is equal in resistance to the first resistor, and which has a first end connected to the common node connected to the first resistor and the second resistor and a second end connected to the mode port of the control circuit;

wherein

the driving circuit includes;

a pull-up transistor having a control end connected to the DATA port of the control circuit, a first end connected to a system voltage, and a second end connected to a common node;

the pull-up transistor being switched into conducting state between the first and second end when the control end thereof receives a high-voltage logic state in the output data from the DATA port of the control circuit;

a pull-down transistor having a control end connected to the second end of the pull-up transistor, a first end connected to an R×

D/NC port, and a second end connected to a T×

D/NC port;

when the mouse is coupled to RS-232 serial port, the T×

D/NC port being connected to the T×

D signal line of the RS-232 serial port;

a resistor having a first end connected to the common node and a second end connected to the second end of the pull-down transistor; and

a diode having a positive end connected to the common node and a negative end connected to the first end of the pull-down transistor;

wherein

the adaptor includes;

a first diode having a positive end connected to the DTR signal line of the RS-232 serial port and a negative end connected to the system voltage input port of the mouse;

a second diode having a positive end connected to the RTS signal line of the RS-232 serial port and a negative end connected to the system voltage input port of the mouse; and

a resistor having a first end connected to the RTS signal line of the RS-232 serial port and a second end connected to the clock signal input port of the mouse;

and wherein

 

when the mouse is connected to PS/2 port, the DATA port of the control circuit is directly connected to the data input port of the PS/2 port, the system voltage input port of the mouse is connected to a voltage signal line of the PS/2 port, the R×

D/NC port of the driving circuit is connected to a first NC signal line of the PS/2 port, and the T×

D/NC port of the driving circuit is connected a second NC signal line of the PS/2 port; and

 

when the mouse is connected via the adaptor to RS-232 serial port, the clock input port of the mouse is connected to the RTS signal line of the RS-232 serial port;

the system voltage input port of the mouse is connected to the DTR signal line and the RTS signal line of the RS-232 serial port;

the R×

D/NC port of the driving circuit is connected to the R×

D signal line of the RS-232 serial port; and

the T×

D/NC port of the driving circuit is connected to the T×

D signal line of the RS-232 serial port.