.LP
The COUNT-LOOP structure is used to create a simple counting loop.  The
following parameters determine its operation.
.IP "Loop Control Variable" 5
Counting (index) variable used to control the looping process.
.IP "Initial Value" 5
Initial (starting) value to be assigned to the loop control variable.
.IP "Increment Value" 5
Increment (step) value to be added to the loop control variable
each time through the loop.
.IP "Final Value" 5
Final (test) value to be used to determine when looping should terminate.
.LP
Values may be constants, defined variables, or expressions. 
(See documentation on `VARIABLES subform' for description of valid 
expressions.)
.SH
EXECUTION
.LP
The first time the glyph is executed (or after a RESET), the `Loop 
Control Variable' is initialized to the `Initial Value' then tested 
against the `Final Value'.
If the `Loop Control Variable' is LESS than or EQUAL to the `Final 
Value', then the appropriate input data is passed to the `Loop Output'
and the loop is executed.  
.PP
To avoid synchronization problems, ALL children of a loop glyph
(those glyphs connected to the COUNT-LOOP output) are 
executed BEFORE the loop glyph is re-executed.
When the execution path returns to
the COUNT-LOOP glyph, the `Increment Value' is added to the `Loop 
Control Variable', and it is compared to the `Final Value', etc.
If the `Loop Control Variable' is GREATER than the `Final Value', then
the appropriate input data is passed to the `Exit Output' and 
execution passes out of the loop.
.SH
COUNT_LOOP USAGE
.IP "Input" 8
The "upper" input arrow corresponds to the `Initial Input' to the loop.
Data on this connection will be passed to `Loop Output' when the loop
is first executed (or after a `RESET').
The `Initial Input' is optional, and thus not required in loops for
which it is not needed.
.IP
The "lower" input arrow corresponds to the `Loop Input'.  The glyph which 
produces the value to be passed back through the loop is connected here to 
indicate the feedback to the loop.  If no feedback is needed, or the initial 
input is to be used on each pass through the loop, the `Loop Output'
should be connected back to the COUNT-LOOP here (see Loop Examples).
.IP "Output" 8
The "upper" output arrow corresponds to the final loop `Exit Output'.  
If further processing is required AFTER the loop, those glyphs are 
connected here.  (The `Exit Output' is optional.)
.IP
The "lower" output arrow corresponds to the `Loop Output' path.  
The first glyph in the loop sequence is connected here.
