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Supersoft/Landmark Diagnostic ROM's for IBM 5150/5155/5160/5162/5170

Source: The ROM's and manual were supplied by Chuck(G) at the VCFF


Introduction

These are best described as ROM hosted motherboard diagnostics.

ROM HOSTED - Instead of the diagostics being on a floppy disk, or on a hard drive, they are on a ROM chip.  You pull out the motherboard BIOS chip, and substitute the diagnostic ROM.
MOTHERBOARD DIAGNOSTICS - These are essentially, motherboard diagnostics - tests of the motherboard.

Floppy hosted diagnostics are expected to be better (a floppy fits more diagnostic code than a ROM), and so ROM hosted diagnostics are good for the situation where the motherboard problem prevents a diagnostics floppy from being booted from.


When to Use Them

Refer to the diagram at here.  The diagnostics are good at detecting the situation where the motherboard's power-on self test (POST) is actually starting, but failing on one of the very early tests, one where the POST gives no indication that the test failed.

I have seen these diagnostics do some weird things (example), some illogical things (examples), and sometimes present results that are completely misleading (example).
That said, these diagnostics have their place in the range of tools and procedures used to identify a problem cause.

Personally, there is only one scenario in which I would use these diagnostics:
• IBM 51xx motherboard that appears to be 'dead'; and
• I know that the motherboard has no short circuits on it (which would overload the power supply); and
• I know for fact that the power supply is good.

Just be aware that the weird/illogical/misleading things that I referred to earlier can lead you to incorrect deductions.


Video Card Requirements

These diagnostics primarily require a CGA or MDA/MGA video card  (although, strangely, an IBM MDA card does not work for the AT version of the diagnostics).
EGA cards will work, but poorly.
Only some VGA cards are expected to work (more information here).

If you do not have a suitable video card, you will be forced to rely on error beeps that the diagnostics send to the speaker.  See 'Speaker' section below.


Speaker

Be sure to connect up a speaker to your motherboard.  Why?  Because these diagnostics send error beeps to the speaker.
If the diagnostics have a problem initialising your video card, the error beeps will at least inform you that the diagnostics are running.

A description of the error beeps is in the user manual (link below).  Beeps for the PC/XT version of the diagnostics are on pages 38 and 39.  Beeps for the AT version of the diagnostics are on pages 40 and 41.

Note that the "System memory at address 00000" description is very misleading.
Some failure examples that produce that error beep pattern:
• First 16 KB tested good.  Problem is in the RAM bank at address 48 KB.
• All motherboardboard RAM tested good. But the diagnostics are trying to test RAM beyond what is fitted.

Relying only on the error beeps is discouraged.  For example, you will not see how much RAM that the diagnostics are trying to test.  For example, in the case of a PC or XT, you will not see if the motherboard switches are being incorrectly read.


Notes

•	Addresses shown on-screen are in hexidecimal and are absolute.  Example: "10000" = 64K  (10000 hexidecimal --> 65536 decimal --> 64K)
•	If a test fails, do not take the test's description literally.  For example, failure of the '8253 TIMER' test may not be due to a faulty 8253 TIMER chip, but instead, due to failure of something that supports TIMER chip operation (e.g. other chips, circuit traces, ...)   The best analogy that I can think of is: On the dash of my car, a red 'battery' light is flashing. Yes, the battery may be faulty, but perhaps the problem is that the alternator is what is faulty, not charging the battery.
•	If these diagnostics show no problems, you must not take that to mean that all motherboard hardware is good, because:    - Not all motherboard hardware is being tested, and    - Some hardware cannot be tested at all by software, and    - Some hardware can only be partially tested by software.

Landmark and Supersoft

So, why does the user manual indicate "Landmark Research International" but the ROM's display "Supersoft Inc"?  Easy.  The Landmark company took over the Supersoft company.


User Manual

Click here for the user manual.


ROM Images

These are images that you use with an EPROM programmer to create the diagnostic ROM/s.

Click here for the IBM 5150.
Click here for the IBM 5155.
Click here for the IBM 5160.
Click here for the IBM 5162.
Click here for the IBM 5170.


Who can burn an image to a ROM/EPROM for you

Some possibilities are shown at here.