Facsimile and static presentation processing – Static presentation processing – Communication
Reexamination Certificate
1999-05-06
2003-02-25
Coles, Edward (Department: 2722)
Facsimile and static presentation processing
Static presentation processing
Communication
C710S316000, C710S008000
Reexamination Certificate
active
06525832
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the priority benefit of Taiwan application serial no. 88205924, filed Apr. 16, 1999, the full disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a computer interface device for periphery device, and more particularly to a dual purpose printer interface device for a printer and a joystick to a host computer, in which the dual purpose printer interface device is used by the printer or the joystick to immediately perform their function once they are plugged in.
2. Description of Related Art
Currently, it is a trend to fabricate a personal computer (PC) to be a greatly reduced dimension with, for example, light, thin and small properties. A portable PC, such as a notebook PC has been a common commercial product already, in which a sub-notebook PC or even a palm PC are also available in the current portable computer products. Even though most of functions of the desk computer are transferred to the portable computer, the portable PC lacks a connector for a joystick, which is commonly used to play computer games in the desk PC. That is because the portable PC is limited by its greatly reduced dimension, resulting in an insufficient space to accommodate a joystick by providing, for example, extra 15 pins for joystick connection. So far, the portable PC usually has no individual connector for the joystick even though the joystick is also fabricated with a reduced size. One conventional solution is that the control functions are installed in the keyboard, typically, on those rare used or even often used keys. This method disturbs the normal functions of the keyboard and also causes an inconvenient use to control the moving direction. Another solution is further proposed as described in U.S. Pat. No. 5,513,302, which provides an interface device with a basic input output system (BIOS), serving as a switch, commonly used by a printer and the joystick. This method needs an action to switch operation modes between driving the printer and the joystick. It may also cause a certain degree of inconvenient use.
FIG. 1
is a block diagram, schematically illustrating a conventional printer interface between a printer and a portable computer. In
FIG. 1
, a printer interface
10
includes a connector
16
that typically has 25 pins, a printer data register
11
, a printer control register
12
, a printer status register
13
, an address-decoder & read/write controller
14
, and a bus driving means
15
. The printer data register
11
includes eight connecting lines PD
0
-PD
7
. The printer control register
12
has four connecting lines: STROBE (STB), AUTO FD XT (AFD), INIT and SLCTIN (CLIN). The printer status register
13
has five connecting lines: ACK, BUSY, PE, SLCT, and ERROR (ERR). The these three registers
11
,
12
, and
13
are electrically connected to the connector
16
, and each of the registers
11
,
12
, and
13
separately receives an address signal from the address-decoder & read/write controller
14
, which also communicates with a potable host computer through address lines AS
0
-SA
9
, and two input/output (I/O) lines IOR and IOW respectively for read and write. The host computer
17
also communicates with the bus driving means
15
, which is connected to the printer data register
11
.
FIG. 2
is a block diagram, schematically illustrating a conventional joystick interface device. In
FIG. 2
, the host computer
17
of
FIG. 1
sends an address to a address decoder
23
through the address lines SA
0
-SA
9
, which is decoded into an enable signal GMCS. The GMCS is compared with an I/O read (IOR) signal and an I/O write (IOW) signal to separately produce a GMRD signal and a GMWR signal. The GMCS signal determines which signal is enabled. If the GMWR signal is enabled, it is sent to an one-shot circuit
22
to first clear voltage set values for the X-axis and Y-axis of a joystick and then start. The one-shot circuit
22
serving as an game interface is coupled to a game port
21
through a resistor PR
3
on four output lines T/A-T/D, which are also respectively coupled to grounded capacitors C
5
-C
8
before the resistor PR
3
. As a result, a RC circuit is formed and is coupled, in series, to the variable resistors (not shown) for the X-axis and Y-axis of the joystick, which is connected on the game port
21
. The charges are gradually accumulated, resulting in a raise of voltage as shown in FIG.
3
.
FIG. 3
is a voltage waveform, schematically illustrating the voltage levels of several control signals varying with the time. In
FIG. 3
, the voltage level of the TA/TB signal gradually rises at time periods C and D, which are also the time periods for game reading operation controlled by a signal D
0
/D
1
. Once the TA/TB reaches a preset voltage value, the one-shot circuit
22
(
FIG. 2
) is triggered and the TA/TB voltage level is reset to zero.
The variable resistors of the joystick can be changed by shifting its X-Y location. By the actual resistance of the variable resistor, the rising slope of the TA/TB is changed. A small shift distance of the joystick causes only a little change of the variable resistance, causing a larger rising slope. The one-shot circuit
22
therefore needs a shot time to be triggered. On the contrary, if the X-Y location shift is large, the trigger time is accordingly long. The trigger time usually varies within a few milliseconds of difference. During the trigger time, the GRMD of
FIG. 2
, continuously exports, such as one per few hundred ns, and reads and accumulates the status of the one-shot circuit
22
. Before the one-shot circuit
22
is triggered, all read status are equal to 1 so that the actual shifted distance of the joystick can be estimated. In this conventional method, the one-shot circuit
22
has to send its data of the joystick shift to a computer bus through a bus driving circuit
24
.
Due to a fact that the current portable computers have no extra space to provide 15 pins for uses of the joystick, how to make use its current available connector for multiple uses so as to include, for example, the function of the joystick is a developing goal. In the U.S. Pat. No. 5,513,302 as mentioned above, the printer connector can be shared with the joystick but it needs a switch action for each time of change. This still gives a little inconvenient as is, so called, user unfriendly.
SUMMARY OF THE INVENTION
It is at least an objective of the present invention to provide a dual purpose printer interface device, which is used by a printer or a joystick to immediately perform their function once they are plugged in. Whether the printer or the joystick are automatically recognized and a desired operation mode is automatically switched by the device.
In accordance with the foregoing and other objectives of the present invention, a dual purpose printer interface device is provided. The dual purpose printer interface device includes at least a printer connector with several pins, a printer interface, a joystick interface, a power generator, a mode selection circuit and a selection device.
The printer connector is used to connect to a printer. The printer interface is used to transmit desired data from a host computer to the printer for printing and printer control signals to the printer. The printer also responds a printer status signal to the host computer through the printer interface. The joystick interface is used to receive action signals from a joystick and accordingly export signals to the host computer. The power generator provides a power source for the joystick. The selection device further includes a first selector and a second selector. The first selector is connected to the host computer, the printer interface, and the joystick interface so that the first connector can connects one of the printer and the joystick to the host computer according to a mode selection signal. The second selector is coupled to the printer connector, the power generator, the printer interface, and the joysti
Coles Edward
Rahimi Alan
Winbond Electronics Corp.
LandOfFree
Dual purpose printer interface device for a printer and a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Dual purpose printer interface device for a printer and a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dual purpose printer interface device for a printer and a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3123710