GB2212306A - Keyboard integrated dataswitch for a personal computer - Google Patents

Abstract

A standalone data communications unit connects up physically and simultaneously to the detachable keyboard of a personal computer unit, the computer base unit itself, and one or more peripheral devices conforming to communications standards RS232C or Centronics (RTM) Parallel Interface. It allows the personal computer user to communicate directly with his printer, plotter or other peripheral device, via his keyboard without the assistance of any special software being run on his computer or without reference to his computer at all. Additionally it provides the personal computer user with an universal and software-independent means of setting up his printer, plotter or other peripheral device, whilst he is running or using any applications software or program on his computer. This is possible via the use of "text" imbedded codes which are externally decoded by the Keyboard Integrated Dataswitch. <IMAGE>

Description

KEYBOARD INTEGRATED DATASWITCH FOR A PERSONAL COMPUTER This invention relates to a Keyboard Integrated Dataswitch for a personal computer.

Dot Matrix. Daisywheel and more recently Laser printers are now a well established part of the personal computing environment.

These peripheral devices along with others such as plotters, are used for producing written or graphical printed information.

They are normallY connected up to a computer via a connection which conforms to one of two internationally recognized communications standards namely EIA RS232C or Centronics parallel interface.

The computer itself or more particularly the Personal Computer is likewise a well established scientific tool around which common standards of use have evolved.

The most common form of Personal Computer consists of a three part desktop unit comprising a keyboard. a base unit (the computer or central processing unit itself). and a VDU (Visual Display unit).

The user communicates with his computer via the keyboard.

The computer processes information input from the keyboard and then if it needs to be printed out sends the information via one of the aforementioned communications links out to the printer or plotter.

The proliferation of computer equipment and their reducing costs, and the use of "wordprocessing" and other software packages has meant that the need and use of the common typewriter has diminished in recent years.

However there are some tasks for which common typewriter functions provide a much faster and better solution than the computer e.g filling in forms, typing on envelopes. short correspondence etc.

The computer with a printer attached is obviously much faster and more agile to use when larger amounts of written information needs to be processed and printed.

The major advantage of the printer over the typewriter is speed, but not only speed. The complexity of the printer and its inherent logical design allows it to produce many more functions than the standard typewriter. For example.

a greater number of typefaces can be accessed, margins, line feed. form feed. tabs, and all print modes associated with a typewriter and much more can be enacted by the use of special commands sent from the host computer via the aforementioned communications link.

Internationally developed standards on the nature and type of commands to be sent - via these communications links - in order to produce a specific printer operation, are now well established and are virtually the same for any printer throughout the world.

However, although these standards are well established there is currently no means by which the Personal Computer operator can use his printer in the same way in which he would use his Typewriter, tapping away at his Keyboard and obtaining instant printout.

Normally. his route or channel to his printer or other peripheral device is through his computer under the control of the "operating system or "applications software In other words, in order to use his printer, he must have his personal computer switched on and be using some additional control software or program.

As mentioned earlier. the emergence of two distinct and one indistinct standard within the computing industrY namelY: i. A registered standard on the communications interfaces EIA RS232C or Centronics parallel for the use of printers and other peripheral devices.

ii. A registered standard on the type of commands (Escape commands) to be sent in order to produce a specific printer operation.

and iii. A bespoke standard on the ergonomic design of a Personal Computer namely using a detachable keyboard.

now makes the design of a Keyboard Integrated Dataswitch possible.

According to the present invention. the essential features of a Keyboard Integrated Dataswitch are that: i. It connects up physically to the keyboard of a personal computer system, the computer base unit itself, and one or more printers or other peripheral devices conforming to the communications standards RS232C or Centronics Parallel interface.

ii. It allows the personal computer user to communicate directly with any printer (conforming to the afore mentioned standards), using his keyboard and printer in a a similar manner to the way in which one would use a standard typewriter without the assistance of any special software being run on his computer or reference to his computer at all.

iii. It allows the personal computer user to directly access and use a printers internal control commands (known as Escape commands) directly from his keyboard using the Esc key and associated character codes. This being done without the assistance or use of any special software running on his computer or without reference to his computer at all.

iv. It provides the Personal computer user with a universal and software independent means for setting up his printer whilst running or using any software, program, or operating system on his computer.

It achieves this by decoding a special reserved character designated from those on his PC keyboard.

This special character when embedded in the body of the text, program. or any other information which is sent to be printed out, will be interpreted by the Keyboard Integrated Dataswitch as the printer control or Escape command, and as such will set up the printer according to the coded information which follows it.

The special character currently being used is the swung dash A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: - Figure 1. Shows how the Keyboard Integrated Dataswitch as configured to the Keyboard, computer and one or more printers. It also indicates the dataflow as viewed from the Keyboard Integrated Dataswitch.

Figure 2. Comprises a block schematic of the major logical workings of the Keyboard Integrated Dataswitch.

Figure 3. Shows a front and rear view of an embodiment of the present invention.

Refering to figures 1. and 3.

The Keyboard Integrated Dataswitch is a stand-alone desktop unit which connects up to a Personal Computer via the keyboard and printer sockets. No additional power source is required to drive the unit.

It was designed specifically to bridge the gap in communications between the PC user and his printer.

The present invention encompasses three switchable modes of use: Typewriter mode Modified Text mode and Standard Mode Common to all three modes is an output control facility which takes the form of a 2 - Way T-Switch. This enables uP to two Centronics parallel printers or RS232C printers to be connected to the computer.

Output from the computer can be steered to either Printer 1 or Printer 2 or both printers simultaneously.

Typewriter Mode In Typewriter Mode, a direct hardware link is set up between the keyboard and printer(s). Input from the keyboard is sent directly to the printer Port selected, bypassing the PC altogether.

Whatever information is on the PC screen at the moment when Typewriter Mode is selected. remains there. PC operation is suspended as the keyboard data path to the PC is inactive in this mode.

In Typewriter mode not only can printable characters be sent directly to the printer. but also all printer control commands.

These can be entered at the keyboard using the Esc key.

Switching back from Typewriter mode to any of the other modes (see below) will not effect the status of the print mode previously set up.

In Typewriter Mode it is possible to use any printer on its own with a Keyboard Integrated Dataswitch and personal computer keyboard, i.e without the need for a computer at all.

An optional voltage adaptor is required instead.

Modified Text Mode (Mod.Text Mode) Modified text mode works in conjunction with the computer and any available program, software or text which appears on the screen.

As the name suggests the text is modified.

In Mod.text mode one single character on the PC keyboard is set aside from normal use and aquires a special meaning.

The character currently being used is the swung dash~.

This special character when sent out to be printed along with normal text is interpreted by the Keyboard Integrated Dataswitch as the printer control or ESC code. and as such it enables the computer operator to embed all printer control commands in the body of his text regardless of the program, software or operating system he is using. A truly universal printer control facility.

Standard Mode This mode provides the PC user with a normal keyboard - Computer - Printer connection. The Keyboard Integrated Dataswitch is transparent. the swung dash character no longer takes on a special meaning, and the keyboard is communicating normally with the computer. However it is still possible to select either printer output port.

Referring to figure 2. Block Schematic In Typewriter Mode, input from the keyboard is synchronised with the master clock on the Keyboard Integrated Dataswitch (KID).

Serial data from the keyboard is clocked into the serial to Parallel Convertor to produce an 8 bit hexadecimal code.

This 8 bit code is presented to a code conversion ROM which translates the information coming from the keyboard into the appropriate character code recognized by the printer.

This information is buffered and sent out to the printer via data latch 2.

Special status contol keys such as Caps Lock, Shift etc are detected and decoded by a special code detect ROM and supporting status decode logic.

Output data is steered to up to two printers or other peripheral devices conforming to the Centronics or RS232C comms standard from the front panel control and switching logic.

In Typewriter mode. the computer input data path is isolated.

i.e there is no link from the computer to the keyboard or printers.

In Modified text mode, data and clocking information from the keyboard are passed directly to the computer.

Output from the computer is sent through Data Latch 1 on the KID to the Keyboard-Printer code translator ROM where the special swung dash character is interpreted and translated as the Escape command. This and other character code data are buffered and output to a printer(s) via Data Latch 2 under control of the front panel switching logic which closes and opens the appropriate latches.

In Standard Mode, data and clocking information is once again sent directly to the computer. Output from the computer is buffered and sent via Data Latch 3 out to the printer(s).

Claims (3)

1. A Keyboard Integrated Data Switch for a Personal Computer comprising a desktop unit which connects up physically and simultaneously to the detachable Keyboard of a personal computer system; the base unit or computer itself; and one or more printers or similar peripheral devices.

Whereby control functions therein provide the personal computer user with the option of communicating directly with the printer. utilising the said keyboard and printer in a similar manner to the way in which one would use a standard typewriter typing at the keyboard and obtaining printout.

This being specifically possible without the assistance of any special software running on his computer or without reference to his computer at all.

2. A Keyboard Integrated Dataswitch for a personal computer as claimed in 1. wherein the personal computer user can directly access and use all of his printers internal control commands directly from his keyboard, this being specifically possible by interpreting the codes sent from the keyboard, without the assistance of any special software running on his computer or without reference to his computer at all.

3. A Keyboard Integrated Dataswitch for a personal computer as claimed in 1. and 2. wherein the personal computer user has a truely universal and software independent means of setting up his printer whilst running or using any applications software, or program on his computer. This universality being specifically possible via the use of "text" imbedded printer command codes which are then externally decoded by the Keyboard Integrated Dataswitch.