Data processing system with integral diagnostic procedure

• US 5,778,170 A
• Filed: 02/14/1996
• Issued: 07/07/1998
• Est. Priority Date: 02/14/1996
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Company (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Chao, Ken
• Primary Examiner(s): DECADY, ALBERT
• Application Number:
  US08/601,410
• Time in Patent Office: 874 Days
• Field of Search: 395/183.01, 395/183.12, 395/183.13, 395/183.14, 395/183.16, 395/183.21
• US Class Current: 714/40
• CPC Class Codes: G06F 11/22 Detection or location of defective computer hardware by testing during standby operation or during idle time, e.g. start-up testing

Abstract

A diagnostic method enables a determination of which of a plurality of data processing modules is at fault in a chain of data processing modules extending between an input and an output. The method includes the steps of reinputting a user (e.g., test) file that has failed to print, to a diagnostic software module which appends a diagnostic indicator to the test file. The diagnostic module and the remaining data processing modules are then operated to process the test file from the input to the output. The diagnostic module monitors operations of the data processing modules and forces one of the data processing modules that is intermediate a first module in the chain and a last module in the chain, to respond to the diagnostic indicator by writing processed results of the test file into a memory file. The diagnostic module then determines if the memory test file exists and, if yes, further checks operations of data processing modules which lie between the intermediate module and the output. If no, the diagnostic module checks operations of data processing modules lying between the intermediate module and the input. In such manner, the diagnostic search begins from an intermediate module in the chain and proceeds in the direction of the fault location.

Claims

1. A method for enabling a diagnostic procedure to determine which of a plurality of data processing modules is at fault in a chain of data processing modules extending between an input and an output, said method comprising the steps of:

inputting a test file to said input, said test file having a diagnostic indicator appended;

operating said data processing modules to process said test file;

operating said diagnostic procedure to monitor operations in a selected data processing module that is positioned in said chain of data processing modules at a point intermediate a first data processing module in said chain and a last data processing module in said chain, said diagnostic procedure responding to said diagnostic indicator by causing an output of said selected data processing module to be stored in a memory test file; and

determining if said memory test file exists and, if yes, further checking operations of data processing modules between said selected data processing module and said output and, if no, checking operations of data processing modules between said selected data processing module and said input.

2. A method for enabling a diagnostic procedure to determine which of a plurality of data processing modules is at fault in a chain of data processing modules extending between an input and an output, said method comprising the steps of:

inputting a test file to said input, said test file having a diagnostic indicator appended;

operating said data processing modules to process said test file;

operating said diagnostic procedure to monitor operations in a selected data processing module that is positioned in said chain of data processing modules at a point intermediate a first data processing module in said chain and a last data processing module in said chain, said diagnostic procedure responding to said diagnostic indicator by causing an output of said selected data processing module to be stored in a memory test file; and

determining if said memory test file exists and, if yes, further checking operations of data processing modules between said selected data processing module and said output and, if no, checking operations of data processing modules between said selected data processing module and said input.

3. The method as recited in claim 2 wherein said test file is inhibited from further transmission along said chain of data processing modules, and is enabled to proceed only if no fault is found between said input and said selected data processing module.

4. A system for determining which of a plurality of data processing modules is at fault in a chain of data processing modules in a network printer system, said system comprising:

a host processor including a plurality of software modules for processing input data, said software modules including a queue control module, an inter-face module, and a network driver module;

a network interface hardware module for connecting said host processor to a network and printers connected to said network;

diagnostic module means present in said host processor for causing input to said queue control module of a test file, said test file including a diagnostic indicator, said diagnostic module means enabling said host processor to commence processing of said test file, said diagnostic module means monitoring an output of an intermediate selected software module to detect a presence of said diagnostic indicator, and upon detecting said diagnostic indicator, causing inhibition of further transfer of said test file and storage of said test file, said diagnostic module means thereafter determining if said test file is present and correct, and utilizing said determining to further decide which direction to further check for a fault.