Control of the muTr calibration system via ArcNet - MJL 9/13/00
===============================================================

Presently this control is via a simple terminal interface.
Later it will change to being controlled from an more intuitive
GUI interface which will implement the same basic functions.

So here is how it works via the simple terminal interface provided
by Andrew's arcNet program which runs on a Windows PC.

- For the board to work it must have the right ArcNet program
  loaded. To load the right arcNet program:
  - Use option "h" to load a hex file
  - select address :  EF (hex)
  - use filename : calib.hex

- Use option "l" for calibration.
- Calibration functions are:
  0. Clear
     - give node id : EF (hex)
  1. Set defaults : sets all channels on first card on (other channels
     off and sets DAC value to maximum.
     - give node id : EF (hex)
  2. Set DAC : set the DAC value (applies to all enabled channels)
     - give node id : EF (hex)
     - give DAC value : between 00 and FF (hex). 0x40 (0xFF) corresponds to
       an output voltage of about 4.6 (17) volts into 100 ohms; and 0x40
       corresponds to an ADC response of about 700 ADC counts.
  3. Set all drivers : sets which channels are enabled on all drivers.
     (One mask is applied to all driver boards. E.g. a mask of 0x01
     would turn on channel one of all boards, while a mask of 0xFF would
     turn on all 8 channels of output on every board. The system is
     designed to drive only 8 outputs at a time; so you should only
     turn on 8 channels total for all boards at once. See also option
     #4 below which allows you to control each driver separately.
     - give node id : EF (hex)
     - give driver mask : 00 to FF (hex)
  4. Set one driver : set which channels are enabled on a particular
     driver board (there are 8 driver boards with 8 channels each for
     a total of 64 channels,
     i.e. (8 octants) x (3 sta-1 + 3 sta-2 + 2 sta-3 anode planes)
     - give node id : EF (hex)
     - give driver mask : 00 to FF (hex)
     - give driver number : 1 to 8

   Channel mapping to detectors:
     - The channels run in ascending order according to plane number, octant
     and station - in that order. E.g. station-1/octant-1/plane-1 is first
     (module 1, output 1) followed by station-1/octant-1/plane-2;
     while station-3/octant-8/plane-2 is last (module 8, output 8).
     Station-1 uses the first 3 boards, station-2 the next 3, and station-3
     the last 2 boards.
     - in the GUI version of the ArcNet control the complexity of this
     map (necessary because of the spare cables that are run) will be hidden
     and it should just be a matter of selecting by station, octant and plane
     which anodes are to be pulsed.

     Station Octant Plane Board Channel
     ------- ------ ----- ----- -------
        1      1      1     1      1
                      2     1      2
                      3     1      3
               2      1     1      4
                      2     1      5
                      3     1      6
               3      1     1      7
                      2     1      8
                      3     2      1
               4      1     2      2

        ......

        2      1      1     4      1
                      2     4      2
                      3     4      3
               2      1     4      4
        ......

        3      7      1     8      5
                      2     8      6
        3      8      1     8      7
                      2     8      8