Browse Prior Art Database

Power Management Method for Portable Personal Computer with Modem

IP.com Disclosure Number: IPCOM000114880D
Original Publication Date: 1995-Feb-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 50K

Publishing Venue

IBM

Related People

Shimotohno, S: AUTHOR [+2]

Abstract

Disclosed is a method for providing an effective auto-answering function for a portable PC with a modem. With this method, a PC system can normally wait for incoming communication while the system is in suspend mode, and automatically judge correctly whether to enter suspend mode again or to keep normal operation (active mode) after the end of the communication.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 86% of the total text.

Power Management Method for Portable Personal Computer with Modem

      Disclosed is a method for providing an effective auto-answering
function for a portable PC with a modem.  With this method, a PC
system can normally wait for incoming communication while the system
is in suspend mode, and automatically judge correctly whether to
enter suspend mode again or to keep normal operation (active mode)
after the end of the communication.

      Fig. 1 shows the I/F between the PC system (*1) and the modem
(*2).  A signal OFFHOOK (*3) is provided in addition to usual RS-232
I/F (*4).  OFFHOOK shows that the modem is in off-hook status.  This
signal is used to detect whether communication is on-going or
terminated.

      Fig. 2 shows the flowchart of controlling auto-answering
function using OFFHOOK signal in comparison with that of not using
OFFHOOK signal.

      After the communication is over, system management BIOS checks
whether any user activity (such as keyboard / mouse operation) has
detected while the system is awake for the communication.  If no
activity, the system immediately enters suspend mode again.  If some
user activity has been detected, the system keeps operation until
idle condition to enter suspend mode is detected.

      If the judgement by OFFHOOK signal is not available, the system
must choose either to enter suspend mode immediately or to keep
operation alternatively.  In either case, inconvenience and
unnecessary wait time i...