Ophis Assembler Tutorial

Part 4: Automatically repeating blocks

In this tutorial we will add a time-delay routine to slow down the
output.  We'll add a subroutine called "delay" that executes 
2,560*(accumulator) NOPs.  By the time the program is finished,
we'll have executed 768,000 no-ops.  

There actually are better ways of getting a time-delay on the C64;
we'll deal with those in part 5.  This code gives us an excuse to
demonstrate the .repeat command.

However.

The .repeat feature actually isn't implemented yet in Ophis.  The
tutor4.p65 file just has 10 NOP commands in its delay loop.  As a
result, there isn't really a lot to discuss here.  Feel free to
look at the source to notice the program structure, since we'll be
modifying it in the next part.  Note the change to the body of the
"greet" macro.

