    DISPLAY OF ANALYZER SAMPLES.      Guide for the program "HEATHDSP.BAS"

    1.	The program asks:  Enter the pathname of the sample file.
	This is the record saved by the logic analyzer, like DEMO.NDL and
	DEMO.DLY.

    The first quarter of samples taken is displayed (Range 0 to 511).
    The yellow cursor is at the far left.  A faint red vertical line may
    be visible and indicates the trigger point used to capture the data.

    Sixteen traces are displayed, labeled on the left from 0 to F (low
    order to high order).

    The solid line towards the bottom is formed by 511 small vertical lines
    marking sample points.  At this expansion level they can not be seen as
    distinct vertical stubs, but just merge together.

    The cursor can be moved in many ways, indicated by a menu below the
    solid white line:
    - End will move the cursor to the far right of the display.
    - Home will move the cursor back to the far left of the display.
    - The left and right arrow will move the cursor one sample
      position at the time.
    - Tab will move the cursor to the right in big steps.
    - Shift Tab will move the cursor likewise to the left.
    Any of these selections will not change the current display, only move
    the cursor.
    The numeric position of the cursor is shown as:   Sample #: xxxx

    - Page up will display the next quadrant of samples (Range 512 to 1023).
      The last range is 1535 to 2046.
    - Page down will make us go back to a previous quarter of samples.

    - At any time can the display start with a known sample number at the
      far left by entering S and the desired number.  Notice that the
      cursor will not automatically move to the far left, but stays at the
      same position in the display, be it that its "sample" # has changed.
      Home will move it "home".

    - At times it may be desirable to expand the traces to observe things
      in more detail.  This is accomplished by entering X and then indicate
      an expansion factor in powers of 2 from a minimum of 1 (no expansion)
      to a maximum of 16.  Command behavior and sample and range numbering
      will adapt automatically.  At higher expansion levels, the solid
      white line will eventually show the distinct sample points.

    - A new file may be loaded by entering L.
    - The program will EXIT when entering Q.


    Samples were taken with a Heathkit IC-1001 Logic analyzer.	This kit
    was purchased from Heath in 1991.  Maximum sample rate is 10Mhz for
    16 parallel traces.
    I built an extender unit for it, which can change this to 20 Mhz for 8
    parallel traces or 40 Mhz for 4 traces.  The extender unit also
    contains a clock switchable between 100 Hz and 40 Mhz.

    The analyzer itself came without a clock and assumed that a clocking
    signal was available in the logic under test.

    The program supplied by Heath with the analyzer was written in Basic
    and compiled.  No source code is available.  The program is good,
    however display of the diagrams requires the unit still to be connected
    to a PC.

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