I suppose "straightforward and easy to write and understand" is in the=20
eye of the beholder.

I do find myself occasionally needing to jump forward to step 14, or=20
backwards to step3,  usually due to a detected mechanical  malfunction. =20
The equivalent  of the dreaded  goto,  I guess.  Convenient, if not=20
actually necessary.

I also sometimes find the same steps in a loop, and I might have:
case 3:
case 12:
    lift_cylinder_up();
    // other things
    extend_step++;
    break;  // back to main

Kerry


Isaac Marino Bavaresco wrote:
> I took some time to study your example S.M. and I think this code is an
> accurate representation:
>
>
> int extend_loop( void )
>     {
>     TaskStart();
>
>     while( 1 )
>         {
>         while( !( tray_at_nest && index_command ))
>             Yield();// Perhaps could be a Sleep to save a lot of CPU time=
;
>
>         set_conv_speed( 256 );
>         tray_feed_pusher( out );
>         Sleep( 200 );
>
>         do
>             {
>             tray_feed_pusher( in );
>             Yield();
>             }
>         while( !forward_slowdown );
>
>         clamp_on();
>         conv_stop();
>         tray_at_ready =3D 1; // tell other tasks we are done
>         }
>
>     TaskEnd();
>     }
>
>
> Adding the two 'Yield' plus the 'Sleep', my code has three exit points
> while your has four, besides during the sleep the function is not called
> at all, making the system faster.
> Besides, my representation is much more straightforward and easy to
> write and understand.
>
>
> Best regards,
>
> Isaac
>
>
>
> Em 16/02/2014 20:20, Kerry Wentworth escreveu:
>  =20
>> Maybe my projects are "simple and small ". but what I do is set up each=
=20
>> loop to do 1 simple task at each entry and return.
>>
>> main()
>> {
>> for(;;)
>>
>> {
>>     extend_loop();
>>     serial_loop();
>>     etcetera_loop();
>> }
>> }
>> extend_loop()
>> {
>> switch(extend_step)
>> {
>> case 0:
>>     if(tray_at_nest && index_command)
>>     {
>>        set_conv_speed(256);
>>        tray_feed_pusher(out);
>>        extend_timer =3D timesince(0);
>>        extend_step++;
>>     }
>>     break;   // Go back to main()
>> case 1:
>>     if(timesince(extend_timer) > 200) extend_step++; // 200mS delay,=20
>> with no waiting
>>     break;   // Go back to main()
>> case 2:
>>     tray_feed_pusher(in);
>>     if(forward_slowdown) extend_step++;
>> // In real life, there would be a timeout here
>>     break;   // Go back to main()
>> case N:
>>     clamp_on();
>>     conv_stop();
>>     tray_at_ready=3D1;   // tell other tasks we are done
>>     extend_step=3D0;   // ready for next tray
>>     break;   // Go back to main()
>> }
>>
>> Each loop runs for a couple of microseconds and returns.  Any task can=20
>> be broken down inro a series of small steps.
>>    =20
>

--=20
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