This chapter contains some tips for using the Micro-Scope to troubleshoot and isolate problems in a computer system.
The first step in solving many computer problems, and often the most difficult step, is to determine whether the cause of the problem lies with the hardware components or with the software, either the operating system or an application.
Hardware Failure is defined as a malfunction of a physical component, either mechanical or electronic. Hardware failures are usually (but not always) consistently repeatable, although some may only occur when the failing part reaches a certain temperature.
Software Failure can be defined as the failure of a program to correctly control the system in which the program is running.
Sporadic, apparently random failures can be either software or hardware. If the problems only show up after the computer has been on a while, they are probably heat-related hardware failure. Hard errors that always occur at a certain point in the execution of a program will probably be software. If the failure disappears when the mix of programs open on the system is changed, then you should suspect a bad memory location, which is a hardware problem.
Micro-Scope has a tremendous advantage over any DOS or Windows-based diagnostic when it comes to separating hardware and software problems. Because Micro-Scope has its own operating system, any problems due to software are automatically eliminated. If a problem still occurs while testing with the Micro-Scope, you can be sure that the cause is in the hardware component being tested. On the other hand, if the hardware tests OK, you can safely say that it’s a software problem, without worrying that the operating system is masking the symptoms.
There are several tools, or ways of approaching a problem, that will help to narrow down the cause.
1. Determine the Nature of the Problem. The first big division, as mentioned above, is whether it’s hardware or software. Once the problem is determined to be software, Micro-Scope is going to be of limited use at best, since it was designed for troubleshooting hardware.
If the problem is hardware, Micro-Scope can be very helpful indeed. If the symptoms point to a particular system component, run tests on that component to pin down the source. If no particular component stands out as a suspect, use Micro-Scope’s batch feature and either Select All or choose a list of all components that might possibly cause the symptoms. This may take a while to complete, but Micro-Scope will run the tests for you and log the results, while you do other work.
2. Suspect the simplest causes. If the symptoms can be explained by one single cause, that is much more likely than an explanation that requires two or more things to be faulty at the same time. And look for the obvious. If the test says a key is stuck, check the keyboard first even though it is theoretically possible for the keyboard controller to give you the same symptoms.
3. Check the easy things first. For instance, if the power isn’t coming on, see that the system is plugged in before you open the cabinet. If a floppy drive is failing, try cleaning the heads before ordering another drive. This may not eliminate all wild goose chases, but at least they will be shorter.
Once the adjustments have been made or the suspect component has been replaced, run the test again and see that the system passes. This step can save much embarrassment and wasted time. We also strongly recommend keeping a log of problems and their solutions. The same type of failures will tend to recur many times during a career, and this type of documentation will become a gold mine of information.
If you are not sure how to make the best use of any feature of the Micro-Scope, or if you feel the results are questionable, please call the appropriate Technical Support line (either your vendor or Micro 2000, Inc.) and get your questions answered.