FCO DELUA-I002, UNIBUS Access Test errors, host time-outs

This Field Change Order (FCO DELUA-I002) addresses critical issues affecting DELUA-M modules at Revision "E2", "E3", or "E4" which exhibit UNIBUS Access Test errors and host time-outs. The problems include power-up self-test failures causing system crashes (in 8300 systems and PDP 1184), LAVC Cluster connection breaks, and terminal server disconnections due to host time-outs.

The FCO, implementing ECO M7521-MK007, outlines a rework procedure with an estimated installation time of 1.0 hour. The solution involves replacing microcode ROMs (P/N 23-451E4-00 and 23-452E4-00) at locations E31 and E56 on the DELUA-M module. After replacing the ROMs, specific Brady Markers ("F" combined with "2", "3", or "4" depending on the original module revision) are applied to the module handle. The procedure emphasizes precautions against electrostatic discharge, orderly system shutdown, module removal, system restoration, running diagnostics (EVDYB or CZUAD), LARS data completion, and updating the Site Management Guide. The FCO was released on February 25, 1988, with parts availability in March 1988.