Hot extraction and insertion of logic boards in an on-line communication system

• US 4,999,787 A
• Filed: 07/15/1988
• Issued: 03/12/1991
• Est. Priority Date: 07/15/1988
• Status: Expired due to Fees

• Current Assignee: Honeywell Bull Incorporated
• Original Assignee: Bull HN Information Systems Incorporated (Atos SE)
• Inventors: Morley, Peter, McNally, Lance, Lotti, James W.
• Primary Examiner(s): Lall, P. S.
• Assistant Examiner(s): MELNICK, STEVEN A
• Application Number:
  US07/219,958
• Time in Patent Office: 970 Days
• Field of Search: 324/158 F, 371/22.1, 371/8.2, 361/397, 364/550, 364/514, 364/900, 340/825.16, 340/825.01
• US Class Current: 710/302
• CPC Class Codes: G06F 11/202 where processing functionality is redundant redundant communication control functionality G06F11/2005, redundant storage control functionality G06F11/2089
• CPC Class Codes: G06F 13/4081 Live connection to bus, e.g. hot-plugging current or voltage limitation during live insertion H02H9/004

Abstract

A real-time, high uptime transaction processing system includes many user terminals communicating with service providers via a communications network. A defective logic board is replaced or a board providing system expansion is installed without powering down the system by providing external auxiliary voltages and a reset signal to the board to put it in a passive state while it is being plugged into or unplugged from its backplane connector. Also under computer control the system is made inactive for a short period of time.

Claims

1. A method of replacing a logic board plugged into a backplane connector in an on-line system without powering down, including the steps of:

A--inserting an end of an umbilical cord into a connector of said logic board to provide auxiliary logic power and a reset signal to disable the logic of said logic board;

B--actuating a hot insert switch to generate a first signal;

C--receiving said first signal by a first computer and sending a hot insert message to a second computer;

D sending a message by said second computer to said first computer to shut down all activity;

E--sending a message by said first computer to said second computer that all activity is stopped, said first computer setting an indicator to a first state;

F--starting a timer in said second computer;

G--removing said logic board from said backplane connector;

H--removing said umbilical cord end from said logic board and inserting it into a connector of a replacement logic board;

I--inserting said replacement logic board into said backplane connector;

J--removing said umbilical cord end from said connector of said replacement logic board;

K--said first computer awaiting said first signal generated by a second actuation of said hot insert switch indicating that said replacement logic board has been inserted into said backplane connector and said second computer awaiting a signal indicating a timeout;

L--responding by said first computer of said second occurence of said first signal or a message from said second computer indicating a timeout to restart all activity and setting said indicator to a second state.

2. A method of adding a logic board to a backplane connector in an on-line system without powering down including the steps of:

A--inserting an end of umbilical cord into a connector of said logic board to provide auxiliary logic power and a reset signal to disable the logic of said logic board;

B--actuating a hot insert switch to generate a first signal;

C--receiving said first signal by a first computer and sending a hot insert message to a second computer;

D--sending a message by said second computer to said first computer to shut down all activity;

E--sending a message by said first computer to said second computer indicating that all activity is stopped said first computer setting an indicator to a first state;

F--starting a timer in said second computer;

G--inserting said logic board into said backplane connector;

H--removing said umbilical cord end from said connector of said logic board;

I--said first computer awaiting by said first signal generated by a second actuation of said hot insert switch indicating that said logic board has been inserted into said backplane connector and said second computer awaiting by a signal indicating a timeout;

J--responding by said first computer to said second occurence of said first signal or a message from said second computer indicating a timeout to restart all activity and setting said indicator to a second state.

3. Apparatus for removing a logic board in an on-line system without powering down comprising:

a power supply for providing a first plurality of voltages and a second plurality of voltages with a reset signal,

a backplane coupled to said power supply for receiving said first plurality of voltages, said backplane including a plurality of connectors,

a plurality of logic boards each coupled to said backplane by one of said plurality of connectors for receiving said first plurality of voltages, one of said plurality of logic boards requiring replacement,

an umbilical cord coupled to said power supply and a first connector on said one of said plurality of logic boards for providing said second plurality of voltages with said reset signal,

said one of said plurality of logic boards including logic means responsive to said reset signal and said second plurality of voltages for remaining in a passive state when unplugged from said one of said plurality of connectors.

4. Apparatus for adding a logic board in an on-line system without powering down comprising:

a power supply for providing a first plurality of voltages and a second plurality of voltages with a reset signal,

a backplane coupled to said power supply for receiving said first plurality of voltages, said backplane including a plurality of connectors,

a plurality of logic boards each coupled to said backplane by one of said plurality of connectors for receiving said first plurality of voltages,

an umbilical cord coupled to said power supply and a first connector on said one of said plurality of logic boards to be plugged into said one of said plurality of connectors for providing said second plurality of voltages without reset signal,

said one of said plurality of logic boards including logic means responsive to said reset signal and said second plurality of voltages for remaining in a passive state when being plugged into said one of said plurality of connectors.

5. Apparatus for replacing a logic board in an on-line system without powering down comprising:

a power supply for providing a first plurality of voltages and a second plurality of voltages with a reset signal,

a backplane coupled to said power supply for receiving said first plurality of voltages, said backplane including a plurality of connectors,

a plurality of logic boards each coupled to said backplane by one of said plurality of connectors, said plurality of logic boards including a plurality of network processor boards, one of said plurality of network processor boards including a hot insert switch, and one of said plurality of logic boards requiring replacement,

an umbilical cord coupled to said power supply and a first connector on said one of said plurality of logic boards to be plugged into said one of said plurality of connectors for providing said second plurality of voltages with said reset signal, said one of said plurality of logic boards having means responsive to said reset signal and said second plurality of voltages for remaining in a passive state,

said one of said plurality of network processor boards including logic means responsive to a signal from said hot insert switch for generating a first message indicating that one of said logic boards requires replacement,

a central processor unit coupled to said logic means of said one of said plurality of network processor boards and having means for receiving said first message for generating a second message, said central processor unit further being responsive to said first message for starting a timer for generating a timer signal after a predetermined time,

said logic means of said one of said plurality of network processor boards being responsive to said second message for stopping bus activity,

said logic means being further responsive to a second occurrence of said signal from said hot insert switch indicating the replacement of said one of said logic boards and the removal of said umbilical cord for generating a third message,

said receiving means of said central processor unit being responsive to said third message if said timer signal was not received, or responsive to said timer signal if said third message was not received for generating a fourth message,

said logic means of being responsive to said fourth message for enabling said bus.