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Known BUGS when the Supersoft/Landmark Diagnostic ROM is fitted to the 16KB-64KB version of IBM 5150 motherboard


BUG: Under no circumstances, believe that a failure of the "16K CRITICAL MEMORY REGION" test must mean that a chip/s in RAM bank 0 has failed.
On a 16KB-64KB motherboard, that test has also been seen to fail when the only failure is in bank 1 (the second bank).
On a 16KB-64KB motherboard, that test has also been seen to fail when the only failure is in bank 2 (the third bank).
   
BUG: 16KB-64KB motherboard:  Sometimes, the DIAGNOSTIC SUMMARY box will show a RAM bit failure by address and bit, but the conflicting text of "NO MEMORY ERRORS" will also be shown.  (Example)
   
BUG: 16KB-64KB motherboard:  When certain multiple RAM bits fail over multiple banks, the DIAGNOSTIC SUMMARY box will show the text of "PARITY ERROR AT ADDRESS 0C000", even though bank 3 may be good.  (Example)
   
BUG: 16KB-64KB motherboard:  Sometimes, a failure in RAM bank 3 (the fourth bank) will not be shown until the failures in RAM banks 0/1/2 are fixed.
   
BUG: If a RAM error at address 05040 is reported, note that the "05040" bit is incorrect. Do not believe the "05040" - the diagnostics have displayed the wrong address.