Power management fault strategy for automotive multimedia system

• US 6,367,022 B1
• Filed: 07/14/1999
• Issued: 04/02/2002
• Est. Priority Date: 07/14/1999
• Status: Expired due to Fees

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Gillespie, Douglas Brian, Wright, David P., Konstantine, John Frank
• Primary Examiner(s): Ray, Gopal C.
• Application Number:
  US09/353,684
• Time in Patent Office: 993 Days
• Field of Search: 713/300, 713/310, 713/320, 713/323, 713/324, 701/1, 701/24, 307/10.1, 307/31, 714/14, 700/286, 322/28, 340/428, 180/54.1, 323/282, 323/285, 320/104, 320/137, 711/112
• US Class Current: 713/300
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode

Abstract

A multimedia/personal computer-based system for operating information, communication, and entertainment devices in a mobile vehicle uses a power management strategy which reduces power consumption and boot-up time in a manner which facilitates use of a complex instruction set computing (CISC) processor system. A power management fault strategy detects fault conditions and restores proper operation without user intervention. A low power microprocessor off-board of the main motherboard switches a plurality of regulated voltages to the main motherboard and other devices. The main application microprocessor on the main motherboard sends periodic status messages to the low power microprocessor. If a time limit between successive status messages is exceeded, then the low power microprocessor takes corrective action such as sending messages to the main application microprocessor, sending a wakeup sequence (resume event) to the main application processor, sending a reset signal to the main application microprocessor, or removing or cycling the regulated voltages being provided to the main motherboard.

Claims

1. A method of powering a vehicle information, communication, and entertainment system which provides mobile operation of information, communication, and entertainment devices in a vehicle, said vehicle having a vehicle powered state and a vehicle unpowered state, said method comprising the steps of:

operating a power management chipset mounted on a main motherboard to control power to a main application microprocessor and a random access memory mounted on said main motherboard;

supplying a plurality of regulated voltages from a power controller and regulator to said power management chipset;

switching on and off said regulated voltages under control of a reduced power microprocessor in response to a user control and whether said vehicle is in said vehicle powered state or said vehicle unpowered state;

periodically transmitting a status message from said main application microprocessor to said reduced power microprocessor during normal full-powered operation of said main application microprocessor;

establishing a predetermined time period in said reduced power microprocessor during which a status message is expected to be received from said main application microprocessor; and

sending a reset signal from said reduced power microprocessor to said main application microprocessor if said status message is not received during said predetermined time period.

2. The method of claim 1 further comprising the steps of:

establishing a further predetermined time period in said reduced power microprocessor after sending said reset signal during which a status message is expected to be received from said main application microprocessor;

cycling said regulated voltages off and then back on to said main application microprocessor if said status message is not received during said further predetermined time period; and

restarting said main application microprocessor.

3. The method of claim 1 wherein, when said main application microprocessor is not in a full-powered operating state, said reduced power microprocessor monitors conditions which should wake said main application microprocessor into said full-powered operating state, and wherein said method further comprises the steps of:

said reduced power microprocessor determining whether said main application microprocessor has correctly assumed said full-powered operating state;

sending a wake-up sequence from said reduced power microprocessor to said main application microprocessor when it has not correctly assumed said full-powered operating state;

resending said wake-up sequence from said reduced power microprocessor to said main application microprocessor if it again fails to assume said full-powered operating state;

cycling said regulated voltages off and then back on to said main application microprocessor if it again fails to assume said full-powered operating state; and

resending said wake-up sequence from said reduced power microprocessor to said main application microprocessor.

4. The method of claim 1 wherein, when said main application microprocessor is in a full-powered operating state, said reduced power microprocessor monitors conditions which should shut down said main application microprocessor into a suspended operating state, and wherein said method further comprises the steps of:

said reduced power microprocessor determining whether said main application microprocessor has correctly assumed said suspended operating state;

sending a shutdown message from said reduced power microprocessor to said main application microprocessor when it has not correctly assumed said suspended operating state;

resending said shutdown message from said reduced power microprocessor to said main application microprocessor if it again fails to assume said suspended operating state;

sending a reset signal from said reduced power microprocessor to said main application microprocessor if it again fails to assume said suspended operating state; and

resending said shutdown message from said reduced power microprocessor to said main application microprocessor.

5. The method of claim 4 further comprising the step of:

turning off said regulated voltages if said main application microprocessor again fails to assume said suspended operating state.

6. The method of claim 1 wherein, when said main application microprocessor is in a suspend-to-RAM operating state, said reduced power microprocessor measures an extended time period after which said main application microprocessor should perform a suspend-to-disk operation, and wherein said method further comprises the steps of:

said reduced power microprocessor determining whether said main application microprocessor has correctly assumed a suspend-to-disk operating state;

sending a wake-up sequence from said reduced power microprocessor to said main application microprocessor when it has not correctly assumed said suspend-to-disk operating state;

sending a suspend-to-disk message from said reduced power microprocessor to said main application microprocessor;

resending said suspend-to-disk message from said reduced power microprocessor to said main application microprocessor if it fails to assume said suspend-to-disk operating state;

sending a reset signal from said reduced power microprocessor to said main application microprocessor if it again fails to assume said suspend-to-disk operating state;

sending a suspend-to-disk message from said reduced power microprocessor to said main application microprocessor; and

turning off said regulated voltages if said main application microprocessor again fails to assume said suspend-to-disk operating state.