Portable computer having dedicated register group and peripheral controller bus between system bus and peripheral controller

• US 5,613,135 A
• Filed: 08/16/1993
• Issued: 03/18/1997
• Est. Priority Date: 09/17/1992
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nishino, Yasuhiro, Oda, Hiroyuki, Uehara, Keiichi, Sakai, Makoto, Tsukada, Hiroyuki, Mamata, Tohru, Dewa, Koichi
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): DARBE, VALERIE A
• Application Number:
  US08/106,724
• Time in Patent Office: 1,310 Days
• Field of Search: 395/800, 395/275, 395/887, 364/DIG. 1, 364/DIG. 2, 364/234, 364/234.4, 364/928, 364/928.6
• US Class Current: 710/62
• CPC Class Codes: G06F 1/1616 with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position
• CPC Class Codes: G06F 1/165 the additional display being small, e.g. for presenting status information
• CPC Class Codes: G06F 1/1677 for detecting open or closed state or particular intermediate positions assumed by movable parts of the enclosure, e.g. detection of display lid position with respect to main body in a laptop, detection of opening of the cover of battery compartment
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: G06F 1/3218 of display devices
• CPC Class Codes: G06F 13/4226 with asynchronous protocol
• CPC Class Codes: G06F 3/023 Arrangements for converting discrete items of information into a coded form, e.g. arrangements for interpreting keyboard generated codes as alphanumeric codes, operand codes or instruction codes

Abstract

Dedicated registers are arranged in a status LCD control gate array connected to a system bus, and the dedicated registers or register group and a keyboard controller are connected through a keyboard interface bus. The keyboard controller has two ports for communicating with a CPU. The keyboard controller transfers existing commands released to an application program or the like and transmits normal key data through the system bus. The keyboard controller transmits hot key data and transfers a command for realizing any other special function through the keyboard interface bus and the dedicated registers.

Claims

1. A portable computer having a CPU, a memory, a keyboard, and a system bus, the portable computer further comprising:

a keyboard controller connected to the CPU through the system bus, the keyboard controller having scan-out I/O ports to which scan lines are connected to transmit, to the keyboard, scan signals, and scan-in I/O ports to which return lines are connected to receive return signals from the keyboard;

a keyboard interface bus including the scan lines and the return lines, and connecting the keyboard controller to the keyboard;

a dedicated register group connected to the CPU through the system bus and to the keyboard controller through the scan lines of the keyboard interface bus, for temporarily storing control information exchanged between the CPU and the keyboard controller;

wherein the keyboard controller writes a hot key data portion of key data in the dedicated register group from the scan I/O port through the keyboard interface bus, the hot key data being formed to set or change an operation mode of the portable computer; and

wherein the keyboard controller transmits remaining key data to the CPU through the system bus.

2. The portable computer according to claim 1, wherein:

the dedicated register group includes a function status register and a system management interrupt (SMI) transmission register;

the keyboard controller writes the hot key data in the function status register and SMI issuance data in the SMI transmission register; and

the CPU reads, in response to the SMI issuance data, the hot key data held in the function status register to perform a hot key function including instant security mode switching, battery save mode switching, switching between resume and boot modes, switching between LCD and CRT display modes, and monochrome inverted display switching.

3. The portable computer according to claim 1, wherein:

the dedicated register group includes a function status register and a request signal register;

the CPU writes the hot key data in the function status register and a request signal in the request signal register; and

the keyboard controller reads, in response to the request signal issuance, the hot key data held in the function status register to perform a hot key function including a function of setting an "Arrow" mode for using a key on the keyboard together with an arrow key, a function of setting a "Numeric" mode for using key on the keyboard together with an arrow key, and a function of setting a "Scroll lock" mode of the keyboard.