Em 17/02/2014 02:35, Kerry Wentworth escreveu:
> I suppose "straightforward and easy to write and understand" is in the=20
> eye of the beholder.


Correct, one becomes accustomed to using a certain programming style and
produces good results with it.
Not to say there are not other styles, some of them simpler and with
other benefits.

=20
> 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.


Indeed, sometimes a well placed 'goto' solves a lot of problems,
simplifies the code and makes it more efficient.
It is easy to put a goto in a co-routine, it is done exactly the same as
in a normal function.


Best regards,

Isaac


> 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 tim=
e;
>>
>>         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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