Change Program Buffering Okuma OSP-300M

Question

I'm currently running a small loop in g-code that has to wait for a common variable to change values. With Program Buffering ON, my g-code program does not see changes to the variables!

What is the best way to turn Program Buffering OFF while I am in this g-code loop?

If I manually set Program Buffering (NC Optional Parameter Bit No.2 Bit 7 to "DOES NOT". Then my loop behaves appropriately and the controller properly checks the value of the common variable each loop.

NLOOP G04 F1
IF[VC890 EQ 0] GOTO NRTS
GOTO NLOOP
NRTS RTS

Very straight forward loop. Maybe it needs to be more complex.
Perhaps if it was longer the buffer wouldn't matter?

I expect my customer's will want Program Buffering turned on.
Can I turn it off temporarily with the THINC API?
Because if it works, this would be great:

public void SetNCOptionalParameterBit(
    int intBitIndex,
    int intBitNo,
    OnOffStateEnum enValue);

If this function will let me set param bit no 2 bit 7 on and off then this would probably be a valid work around.

Okuma.CMDATAPI.DataAPI.COptionalParameter myCOPtionalParameter;
myCOptionalParameter = new Okuma.CMDATAPI.DataAPI.COptionalParameter();

myCOPtionalParameter.SetNCOptionalParameterBit(2, 7,
    Okuma.CMDATAPI.Enumerations.OnOffStateEnum.On);    

Answer 1

The best solution for my scenario was saving the current value of NC Optional Parameter 2 into a common variable, then changing it to Does Not buffer then running my code, then putting it back to whatever it was before.

in Gcode:

VC892 = VOPRB[2] (save current NC Optional Parameter bit 2 value)
VOPRB[2] = [VOPRB[2] OR 128] (bit magic to flip bit 7 to a 1 if its not)
(insert code to be run without buffering)
VOPRB[2] = VC892 (put back saved NC Optional Parameter bit 2 value)

Answer 2

The SetNCOptionalParameterBit() function is capable of setting NO. 2, BIT 7.

However, depending on what version of API you have, the THINC API test application might fail to do so. I confirmed there is a bug in the test app for API 1.17.2.0. And it was fixed by the time 1.18.0.0 was released.

So just be aware of that. Even if your machine has an older API such as 1.17.2.0, you should still be able to write code that uses this function successfully. Just ignore the test app results.

Answer 3

What about M331 to prevent read ahead? (I won’t be at a control for a few days to verify usage, I’m holding my newborn and it’s 4am right now but I think it can go either on the line where you read variable on or the line before.)

NLOOP G04 F1 M331 (buffering prohibit)
IF[VC890 EQ 0] GOTO NRTS
GOTO NLOOP
NRTS RTS