5/10/99
                                                        B.Baldin

    Minimum requirements for 1553 bus interface implementation
    ==========================================================

1. This  document   describes  minimum  mandatory   requirements for the
   implementation   of the  1553 bus   interface in  the muon  front-end
   controllers   design.  The muon  front-end   controllers  include PDT
   Control Board  (CB), Scintillator  Readout Card  (SRC) and Mini-Drift
   tube Readout Card (MDRC).

2. In order to satisfy intersystem compatibility the following features
   have to be implemented in the muon front-end controllers:

    - two bridged Thrompeter triplex connectors with no termination
      (located on the front-panel for VME-based units)

    - an LED  indicator  for "valid  word"  signal detected  by the 1553
      interface (located on the front panel for VME-based units)

    - an LED  indicator  for "timeout  reset"  signal (see  muon monitor
      board schematic, located on the front panel for VME-based units)

    - a five bit Remote Terminal (RT) address switch to select RT address
      (located on the PCB)