In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Sparks-R-Fun wrote:

John,

  Perhaps you can write similar programs on the BS-2 and SX to generate stepped sine waves through the use of lookup tables.  Insert adjustable pauses into each each program to alter the output frequency.  Have the students adjust the length of the pauses either via pushbuttons or serial input.  You may want to compare the waveforms on an oscilloscope.  

   For low frequencies (those with long pauses between table lookups and output value changes), the waveforms should be roughly similar.  As the frequency increases (while the corresponding pause between updates decreases) it should become increasingly evident that the BS-2 is spending much more time "between pauses" than the SX.  When the pause is reduced to zero, both devices will have reached their maximum cycle speed for the program.  This should be evidence by the SX displaying a much higher frequency and over all a larger frequency range.

   Now, if you really want to nail the point home, create another program that uses interrupts on the SX to allow it to send serial data in the foreground (a BS-2 taunting message perhaps) while the above waveform generation process happens smoothly in the background.  Let's see a BS-2 do that!

   Whatever you create, be sure to share it with us.  We all like to show off what our SX's can do from time to time!  ;)

 - Sparks

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