Digital Output Cycle Rate? | LabJack
 

Digital Output Cycle Rate?

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Mr. Bologna
MrBologna's picture
Digital Output Cycle Rate?

Hello,

I am considering using a T4 as an interface between a PC script and a stepper motor with an integrated driver.

The integrated driver is controlled via 5V pulse (step command) and I am currently using an arduino for this signal.

The step resolution on the motor is variable, but I currently use it at the max resolution of 25,000 steps/revolution (micro-stepping). I could tune this down all the way to 200 steps/rev if I need to.

Say I want to move at a speed of 100 RPM, this puts me at a 0.000012s duty cycle.

I just want to know if the T4 is capable of toggling its digital outputs at a rate that will allow me to use a high step resolution like this.

LabJack Support
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The time for your software to

The time for your software to send a command to the T4 and get back the response is roughly 1 ms, so you cannot use command-response mode to toggle a bit one toggle at a time and get that done every 6 us.  Perhaps a timer would work for you?  Start here and this might generate more questions:

https://labjack.com/support/app-notes/waveform-generation

 

Mr. Bologna
MrBologna's picture
Could it be done utilizing

Could it be done utilizing the hardware Lua scripting?

Something like: I trigger the script via the software > it cycles the step output until it recieves a stop command (digital input) > I get a "done" message in the software?

LabJack Support
LabJack Support's picture
Sounds like a loop executing

Sounds like a loop executing around 100k.  Simple untimed Lua scripts can do 10s of k but not 100k.  Anyway, what you are describing sounds perfect for a DIO-EF (aka timer) that you just control from your host software (or from Lua script if that makes sense for some reason):

https://labjack.com/support/datasheets/t-series/digital-io/extended-features/pulse-out