ProTool, changing of memory bit

I know you can say to me RFTM, but please sorry to me.
My question: I want to change value of memory bit (when button FX is pushed memory bit M171.1 is true, when I cancel push button Fx memory bit M171.1 is false
(in Step7 M171.1 (symbol name is "Button_OP_panel") is used
A "Button_OP_panel"
L S5T#2S
SD "Timer_button"
A "Timer_button"
= "M_Button_Reset"
A "M_Button_Reset"
AN "M_reset"
JC CYCL

Thanks in advance for answer (sorry for bad english)

In Protool: Open System .. Screen/keys.
Click the button you want to assign the "reset" function.
Select one of the functions:
- Set bit.
- Set bit in tag.
- Set bit while keypressed.

I would use "set bit" and evaluate the tag in the PLC with a oneshot.
When the oneshot is activated I would do the resetting AND set the bit back to zero.
In that way your system cannot hang if there is a comms failure, and even a short keypress will be detected properly.

I did this
Function key F1->Functions->Function selected/Tag set value=1 (MB172)next branch of tree Tag set value=0(MB172)
And what I get: when I touch F1 MB172 change to 1 and (I think after OP is cycle 1s) then change to 0.
But I want that MB172 change to 1 when I push F1 and change to 0 when I cancel pushing. (And I can't change M172.0 to true and false because I did't found this option, only for byte I found one)

Thats the reason why you should only use one "set bit" function.
Then evaluate the bit in the S7 program, and reset the bit in the S7 program.
Its the most robust way to do it.
Its a bad idea to try to make a timed impulse from the Operator panel.