MCB interface to 85-foot antennas.

A.  Antenna monitor addresses (relative to start address)

  1.  analog monitors: 2-s complement signed numbers, low order 12 bits
	are significant.  Full scale (hex 7FF) corresponds to 10 volts.

 hex address     description
 -----------    ----------------------------------------------
   2            focus in mm = V x 100
   3            polarization in degrees = V x 100
   4            supply pressure in psi = V x 100
   5            return pressure in psi = V x 50
   6            refrigerator drive current in amps = V x 1.333
 -------------------------------------------------------------

  2.  digital monitor words:

  hex address   description
  -----------   ------------------------------------------------
   18           Hour angle: 2s complement, full scale(7FFF) = 6 hours.
   19           Declination: 2s complement, full scale(7FFF) = 90 deg.
   1A           brake and limit status bits.
  --------------------------------------------------------------

	bits in word 1A
	---------------
	bit    description
	---   ----------------------------------
	 0    North limit (if bit set)
	 1    South limit     "
	 2    East limit      "
	 3    West limit      "
	 4    polar brake (bit set means brake off)
	 5    declination brake (bit set means brake off)
	 15   set=local control; reset=computer control
        -------------------------------------------------


B.  Antenna command addresses.

    hex address   description
    -----------   ---------------------------------------------------
      10          motor control word (lower byte controls polar axis,
			upper byte controls declination axis.)
      11          brake, polarization, and focus control
    ----------------------------------------------------------------


     1.  Motor control word (address hex 10)
         ----------------------------------
         bit   description
         ---   -----------------------------------
          0    if set, slew east
          1    "   " , slew west
          2    "   " , run scan A east (rate 1.0)
          3    "   " , run scan A west (rate 1.0)
          4    "   " , run scan B east (rate 1.4)
          5    "   " , run scan B west (rate 1.4)
          6    "   " , run scan C east (rate 1.6)
          7    "   " , run scan C west (rate 1.6)

          8    if set, slew North
          9    "   " , slew South
         10    "   " , run scan A North (rate 1.0)
         11    "   " , run scan A South (rate 1.0)
         12    "   " , run scan B North (rate 1.4)
         13    "   " , run scan B South (rate 1.4)
         14    "   " , run scan C North (rate 1.6)
         15    "   " , run scan C South (rate 1.6)
	 ------------------------------------------

    2.  misc control word (address hex 11)
	-----------------------------------
	bit   description
	---   ------------------------------------------
	 0    if set, run focus down
	 1    "   " , run focus up
	 2    "   " , run polarization counter-clockwise
			  (as seen looking down from above)
	 3    "   " , run polarization clockwise.
	 4    "   " , release stow brakes.
	      "  reset, set stow brakes.

        15    if reset, do emergency stop.
	-----------------------------------------------

---

GBI RECIEVER INTERFACE FOR 85-1 and 85-2.

Monitor points
--------------
Rel.addr. parameter           units
--------- -----------------  ------------
 0x08     SL total power      volts
 0x09     SR total power      volts
 0x0A     XL total power      volts
 0x0B     XR total power      volts
 0x0C     SL expanded power   volts
 0x0D     SR expanded power   volts
 0x0E     XL expanded power   volts
 0x0F     XR expanded power   volts
 0x10     SL gate voltage     volts
 0x11     SR gate voltage     volts
 0x12     XL gate voltage     volts
 0x13     XR gate voltage     volts
 0x14     SL LO level         volts
 0x15     SR LO level         volts
 0x16     XL LO level         volts
 0x17     XR LO level         volts
 0x18     Vac-Ion pump        log(torr) = (V/3) -9
 0x19     Box Temp            degC = v*100 - 273
 0x1A     32v pwr. sup.       volts = v*64
 0x1B     24v pwr. sup.       volts = v*4.8
 0x1C     -5v pwr.sup.        volts
 0x1D     +5v pwr.sup.        volts
 0x1E     -15v pwr.sup.       volts = v*3
 0x1F     15v pwr.sup.        volts = v*3
 0x23     Sband LED level     volts
 0x24     Xband LED level     volts
 0x25     50K temp            degK = v*100 - 5
 0x26     15K temp            degK = v*100 - 5
 0x27     Vac. voltage        volts
 0x28     digital flags
---------------------------------------------------


Digital flags (address 0x28)
----------------------------
  mask    parameter
 -----  ---------------------------------------------------------
   1     optical laser current monitor (=1 if normal; =0 if high)
   2     receiver optical level (=1 if normal; =0 if low)
   4     XR LO lock (=0 if locked)
   8     XL LO lock (=0 if locked)
  16     SR LO lock (=0 if locked)
  32     SL LO lock (=0 if locked)
  64     100 MHz lock (=0 if locked)
 -----------------------------------------------------------------

------------------------------
Commands: send to address 0x30
------------------------------
 mask     parameter
 ----   ------------------------
   1     SR LO (1=on)
   2     SL LO (1=on)
   4     XR LO (1=on)
   8     XL LO (1=on)
  16     Noise Mod (0=off; 1=on)
  32     Xcal (0=on; 1=off)
  64     Scal (0=on; 1=off)
 -------------------------------