
	 PLOT.TXT - byte offsets

	-------------------------------------------------
	|15 14 13 12|11 10  9  8| 7  6  5  4| 3  2  1  0|  PC  bit numbering
	------------|-----------|-----------|-----------|
	| 0  1  2  3| 4  5  6  7| 8  9 10 11|12 13 14 15|  UUT bit numbering
	-------------------------------------------------

     NORMAL MESSAGES

     byte  1 RTtoBC   2 BCtoRT   3 RTtoRT   4 MCw/o    5 MCxmt    6 MCrec
     ----  ---------  ---------  ---------  ---------  ---------  ---------
      00   |  LBW  |  |  DW1  |  |  TCW  |  |  LBW  |  |  LBW  |  |  DW1  |
            ---------  ---------  ---------  ---------  ---------  ---------
      02   |  MSW  |  |  DW2  |  |  LBW  |  |  MSW  |  |  MSW  |  |  LBW  |
            ---------  ---------  ---------  ---------  ---------  ---------
      04   |  DW1  |  |  DW3  |  |  MSW  |             |  DW1  |  |  MSW  |
            ---------  ---------  ---------             ---------  ---------
      06   |  DW2  |  |  DW4  |  |  DW1  |     where:
            ---------  ---------  ---------
           :       :  :       :  :       :     TCW = transmit command word
           ---------  ---------  ---------     RCW = receive  command word
     2n-2  | DWn-2 |  |  DWn  |  | DWn-3 |     TMC = tramsmit mode code
           ---------  ---------  ---------     RCW = receive  mode code
      2n   | DWn-1 |  |  LBW  |  | DWn-2 |     RBC = receive  broadcast
           ---------  ---------  ---------     TBM = transmit broadcast mode
     2n+2  |  DWN  |  |  MSW  |  | DWn-1 |     RBM = receive  broadcast mode
           ---------  ---------  ---------     MSW = mux sataus word
     2n-4                        |  DWn  |     DW  = data word
                                 ---------     LBW = loop back word
     2n+6                        |  MSW  |
                                 ---------


     BROADCAST MESSAGES

     byte  7 BCtoRTs  8 RTtoRTs  9  MCw/o   10 MCrec
     ----  ---------  ---------  ---------  ---------
      00   |  DW1  |  |  TCW  |  |  LBW  |  |  DW1  |
            ---------  ---------  ---------  ---------
      02   |  DW2  |  |  LBW  |             |  LBW  |
            ---------  ---------             ---------
      04   |  DW3  |  |  MSW  |      Note:
            ---------  ---------
      06   |  DW4  |  |  DW1  |      The 1553 interface card deposits 16
           ---------  ---------      bit data into memory in the correct
           :       :  :       :      PC order, lsbs 1st (even byte).
           ---------  ---------
   2n-2    |  DWn  |  | DWn-3 |      UUT 32 bit data is deposited MSH then
           ---------  ---------      LSH, which is PC word backward. The
     2n    |  LBW  |  | DWn-2 |      data reduction routines swap the
           ---------  ---------      2 words for items > 16 bits.
   2n+2               | DWn-1 |
                      ---------
   2n+4               |  DWn  |
                      ---------
