公开(公告)号：WO1990016029A1

公开(公告)日：1990-12-27

申请号：PCT/US1990002985

申请日：1990-05-30

Applicant: GRID SYSTEMS CORPORATION

Inventor： GRID SYSTEMS CORPORATION ,  COLE, James, F. ,  MCNAMARA, James, H.

IPC: G06F15/00

CPC classification number: G06F1/3228 ,  G06F9/463

Abstract: A method and apparatus for configuring a computer in a low-power mode are provided. In the low-power mode, dynamic random access memory is refreshed by a battery powered system in order to maintain the memory contents. Low-power mode is entered by saving an interrupt mask (48) and by disabling interrupts (50), followed by saving the DMA status (56), finishing DMA operations (54), and disabling DMA (58, 60). After these steps, the I/0 state of the machine is saved by saving various I/0 registers and ports. A refresh of the memory is forced before the system refresh operations are discontinued.

公开(公告)号：WO1992000638A1

公开(公告)日：1992-01-09

申请号：PCT/US1991004417

申请日：1991-06-21

Applicant: GRID SYSTEMS CORPORATION

Inventor： GRID SYSTEMS CORPORATION ,  COLE, James, F. ,  KEERAN, Jerald, J.

IPC: H04K01/00

CPC classification number: G06F21/31 ,  G07C9/00142

Abstract: A method and apparatus for password protecting a personal, laptop or single user computer. The user's password entry (34) is compared to the value of a secondary password (58) retained by the computer as well as the value of the user's stored primary password (44a). The user may thus access the computer when his primary password is corrupted or forgotten by obtaining an alternate password from the computer manufacturer which matches the secondary password generated or stored by the computer. The operation of the method and the organization of the apparatus make the secondary and alternate passwords valid for a limited time, thereby preserving the overall integrity of the password protection system. The primary, secondary and alternate passwords may be encrypted (40 & 56) for added security.

公开(公告)号：WO1990016030A1

公开(公告)日：1990-12-27

申请号：PCT/US1990002986

申请日：1990-05-30

Applicant: GRID SYSTEMS CORPORATION

Inventor： GRID SYSTEMS CORPORATION ,  HAWKINS, Jeffrey, C. ,  DULANEY, Kenneth, L. ,  DALY, John, J. ,  MC NAMARA, James, H. ,  COLE, James, F.

IPC: G06F15/00

CPC classification number: G06F1/3228 ,  G06F9/463

Abstract: A hand held computer (10) of a type used for such activities as taking inventory, recording signatures on delivery, keeping a route agenda, etc. has a large screen (12) and preferably is without a built in keyboard. The tablet type computer is thin in profile, light in weight and is easily carried and used. Programming in the computer enables an operator to select from various forms available for display on the screen (12), enables character recognition for items printed on the screen (12) using a conductive stylus (29), enables the recording in memory of signatures, graphics or any other material entered on the screen, and enables other convenient functions. Certain preferred features of the computer enable it easily to be converted into a full function desk top computer with a keyboard, expansion module and stand.