tx_event_flags_get don't trigger if ULONG *actual_flags_ptr is NULL

[ABasi.2]

Hi 

i have a question about tx_event_flags_get function

i was using the function like this: 

 

 

 

tx_event_flags_get(&Flags, 0x01, TX_OR ,NULL, TX_WAIT_FOREVER);

 

 

with a NULL -> ((void *)0) for the actual_flags_ptr parameter and worked fine , i 'm using NULL beacuse i don't need the actual value of the flags

 

after that i'have tried to use like this:

 

 

if(tx_event_flags_get(&Flags,0x08, TX_OR_CLEAR ,NULL, TX_NO_WAIT) == TX_SUCCESS)

 

 

but it seems the combination of NULL and TX_NO_WAIT option is not working, never triggered

 

then if i use an actual variable pointer like this:

 

 

if(tx_event_flags_get(&Flags, MACHINEPARAMSRESET, TX_OR_CLEAR ,&actualFlag, TX_NO_WAIT) == TX_SUCCESS)

 

 

work perfect.

 

why i cannot use NULL if i'm using TX_NO_WAIT ?

there is a problem with the NULL pointer?

i'm also using the qwueue info get like this: 

 

 

 

tx_queue_info_get(&queue, NULL, &queueCnt, NULL, NULL, NULL, NULL);

 

 

and it's working perfectly

 

am i wrong to use the NULL pointer ehere i don't need the value?

 

thank you

[Amel NASRI]

Hi @ABasi.2,

May you give more details on the context of your question please? Is it ThreadX related like your other question are printf, fprintf, scanf etc threadSafe in threadX?

-Amel

[ABasi.2]

Hello!

its threadX related,

my question is about the use of NULL instead an actual pointer to a variable to store the flags value

 

in most case i don't need to know the actual value of the flags,  i don't want to use an actual variable so i use the NULL pointer instead a pointer to a variable

 

like in this example : 

 

tx_event_flags_get(&Flags, 0x01, TX_OR ,NULL, TX_WAIT_FOREVER);

 

the firmware wait at this line forever the flag in position 0x01 to be setted 

this works fine 

 

but if i try this instead:

 

if(tx_event_flags_get(&Flags,0x01, TX_OR_CLEAR ,NULL, TX_NO_WAIT) == TX_SUCCESS)
{
// some code
}

 

don't work anymore..

 

the differences are the TX_NO_WAIT and the fact i'm checking in a IF statement and the TX_OR_CLEAR

 

but if i use an actual variable instead the NULL pointer like this:

if(tx_event_flags_get(&Flags,0x01, TX_OR_CLEAR ,&flagsValue, TX_NO_WAIT) == TX_SUCCESS)
{
// some code
}

 

 

this works!

why? i don't need the flags value to be stored in flagsValue variable

 

thank you