« Close

Datasheets and User Guides

App Notes

Software & Driver - System Timer Low/High Read (Modes 10 & 11)

The LabJack U3 has a free-running internal 64-bit system timer with a frequency of 4 MHz. Timer modes 10 & 11 return the lower or upper 32-bits of this timer. An FIO line is allocated for these modes like normal, even though they are internal readings and do not require any external connections. This system timer cannot be reset, and is not affected by the timer clock.

If using both modes 10 & 11, read both in the same low-level command and read 10 before 11.

Mode 11, the upper 32 bits of the system timer, is not available for stream reads. Note that when streaming on the U3, the timing is known anyway (elapsed time = scan rate * scan number) and it does not make sense to stream the system timer modes 10 or 11.

Note that system timer runs at 2MHz on U3 hardware 1.20.



Is there some example to using timer mode 10/11? I am trying to create a program using visual basic with the labjack. One part is that i need to know how many pulses are read by the labjack counter during a certain amount of time (where the amount of time is set by the user). I can use an external timer to get this done but I assumed using the internal timer with the U3 would be the better idea. I just do not know the proper way to write the code.




(I tried posting this to the frequency measurement forum but it didn't let it through without creating an account, something I dont think I need to do. So please don't just send me back to that forum. Thanks)

Check out the Visual Basic example archive here: http://labjack.com/support/ud/examples