feedhold in a macro.

[Battwell]

just wondering on adding feedhold to my toolchange macro using something like below is going to cause problems.
adding before some movements

while(exec. getled(217)); // is feedhold on led
{exec.wait(10);}

can anyone see a problem with this?
i dont want to use stop- as i have that to jump out of the macro if i have a snarl up
the program runs a series of output switched pneumatic ram movements. id like to have the toolchanger pause sequencing if in feedhold
(only has a few controlled xyz axis movements - which will hold but these are at the start and end)

[Battwell]

ok. i did some testing- and after loads of compile errors came up with this.
still something i cant work out.
at the end i use the function is macro stopped to clear the output if the stop button has been pressed.
but it switches off anyway- and the button has not been pressed ? (unless stop button led flag doesnt toggle until a cycle start is initiated?)
i couldnt find an led to check for stop.
i want the output to stay on unless the macro was stopped using stop button. ie if the loop is finished by feedhold release.

otherwise- i think its going to be ok.
could someone please test?
pasted below:

//waits and repeats while feedhold is true and stop button not pressed
//otherwise exits when feedhold is switched off- or stop button is pressed
//ps- this took me hours to write! brendon
int Chuckopenport=3;
int Chuckopenpin=3;

bool hold= (AS3.GetLED(217));// is feedhold active

//***start of test loop***//

do{
hold= (AS3.GetLED(217)); //must be re checked inside the loop
if(hold){ // this would be reversed in a real program (not)
exec.Setoutpin(Chuckopenport, Chuckopenpin);} // Open the chuck with pneumatic valve
exec.AddStatusmessage("feedhold "+hold); //confirming hold led status for debugging
exec.Wait(1000);
}while ((hold)&&(!exec.Ismacrostopped())); //and

//***end of test loop***//

exec.Wait(100);
if(exec.Ismacrostopped());
{
exec.Clroutpin(Chuckopenport, Chuckopenpin);
}

[Battwell]

i put a status message checking ismacrostopped just before the clear output - and it shows as false.
- so it should not run the if loop clearing the output?

[Battwell]

can anyone explain to me why- changing the last few lines to this makes it work ??
ive always used { } brackets around my if statements before

//***end of test loop***//

exec.Wait(100);
stopped=(exec.Ismacrostopped());
exec.AddStatusmessage("stopped?= "+ stopped);
if(exec.Ismacrostopped())
exec.Clroutpin(Chuckopenport, Chuckopenpin);

[cncdrive]

The issue is the ; and not the brackets.
You placed a ; after the if statement and so that closes the statement and so the next line will be out of the conditional check.

The

Code: Select all

if(exec.Ismacrostopped())
//Do something


and the

Code: Select all

if(exec.Ismacrostopped());
//Do something


are not the same.
In first case the Do something will be executed if the statement is true and in second case the Do something will be always executed.

[Battwell]

Thank you
Now you can see why writing macros takes me so long!
I only learnt the first basic language when I was in school 36 years ago!

[Battwell]

i simplified it to this

int port=3; // output to activate
int pin=3;
int holdled=217;
bool hold= (AS3.GetLED(holdled));
//
//
while (hold){exec.Wait(1);hold= (AS3.GetLED(holdled));}; // wait here if feedhold is on. does nothing if feedhold is off.


//continuing here//
// eg.
exec.Setoutpin(port, pin);
exec.Wait(2000);
exec.Clroutpin(port, pin);

[Battwell]

the above only worked on the first instance of it in a macro- unless the hold was checked just before it.
changing it to a do while loop makes it execute at least once- hence checking the condition of hold inside the loop before evaluating .
(every day is a school day for me)
so this example is better .

do {exec.Wait(1);hold= (AS3.GetLED(217));}while (hold);