the bits status in PLC

When we use the third software send the information to PLC, just as VB or other applications. always we send the package include the PLC address and the value.
for example:
we use AB PLC5, and the third application send the package to PLC5.
address :B10:1
data : 0001 ( HEX)
so please tell me the below opinion is true or not?
1. B10:1/0 will equal to 1;
2. after the scan , B10:1/0 will change to 0 ;
thanks a lot !

When sending data to a AB PLC5 from third party software such as Visual Basic, I believe the bit will stay a 1 after the scan.

thanks !

Whether there has a software that send the value to PLC and only hold one scan?

Because in my system , it seems that the valve can't hold on until this bits has been unlatched.

If you only want a bit on for one scan, then use a One Shot. You might need to use the B10:1/0 to turn on another bit set up as a One Shot. You will need to add a rung.
AB experts, please post an example. I'm not an AB man.

The external software cannot guarantee that a bit which is set will remain only for one scan. If it again writes a zero it would probably be after more than one scan. There must be logic inside the PLC which assures that the information (the '1') is only acted on once.

Thanks your kindly help!

I think , external software only send the value to the PLC. the bit stauts remaines one scan or before next value changed controlled by the PLC logical not the external software.

by the way,sometimes when external software communicated with PLC. the package may lost. can we have a way to monitor the package flow ? for example ,Can we get a excel file to record the bits change information?

Thanks!

The commands should be SET and RESET. SET to turn a bit on, RESET to turn a bit off. The bits won't change unless your PLC program changes them.
Communications should be monitored on your computer. There are several serial sniffer programs available. Many are free. This one looks good.