VISA

[Jon_Boustani]

Hey LabView community,

I am currently working on a project that involves an ultramotion linear actuator (EMA). We have sucessfully communicated to the actuator using Putty and a serial-USB adaptor to send serial commands, however, when we try to communicate using a VISA example provided by LabView, the actuator will not respond to commands. We were wondering if there was a syntax error i.e. carriage characters like \n or \r that we need to type into the LabView command window to get the actuator to respond. If anyone has any idea how to fix this or can provide a file that is able to communicate to an EMA through serial commands, that would be very appreciated!

Thank you!!

[crossrulz]

---

Jon_Boustani wrote:  We were wondering if there was a syntax error i.e. carriage characters like \n or \r that we need to type into the LabView command window to get the actuator to respond.

---

That sounds like the most likely problem.  Are you using the Termination Character feature of VISA?  If so, you can use a property node to set the Serial Settings:End Mode For Writes to be TermChar.  This will have VISA add the termination character to the end of all writes that you perform.

[Jon_Boustani]

We have tried thr termination character feature in all combinations and have tried various termination characters in hex, ASCII, and binary. I will attach oyur current code below, maybe we are missing something. We have also tried communicating through NI MAX with no result

[Jon_Boustani]

sorry for all the typos...

[johnsold]

What does the external device require for a termination character?  There are no standards for how to terminate messages in RS-232 so you need to read the manual or get the information from the vendor.  Until you (and we) know what the instrument expects, we cannot tell you what is wrong.

Lynn