Passing parameters from LabVIEW vi to TestStand

[kech]

Hallo,

I'm struggling with retrieving the value of a vi OUT Parameter of type ASCII string from the basic_serial_write_and_read.vi (http://zone.ni.com/devzone/cda/epd/p/id/2669)

I've assigned a Local Variable type string and assigned this expression to the vi OUT parameter "read string".

When running the sequence however, the Local Variable value is not updated! (?)

I can see the ASCII string being returned from the UUT on the NI I/O Trace tool.

The basic_serial_write_and_read.vi works OK in LabVIEW.

I'm just getting started but can't figure this out. I'd be appreciative of any hints.

Cheers

Kech

[crossrulz · Accepted solution]

Step into your VI from TestStand and make sure it is running correctly.  Can you attach some code?

[kech]

Attached are the basci_erial_write _and_read.vi and my play.seq TestStand sequence.

When using the ASCII char "@" as string to write value - i get no reply value to the Locals.Local_read Variable, although i see that the UUT replies with a 22 byte long message on the NI I7O Trace tool.

How do i convert the vi - so that the string to write and read string parameter type can be used with hex data i.e. 0x40?

[kech]

Hi,

I've made some progress - with a RS232 loop back test - established that the ASCII string write is being received and passed to the Local Variable Local_read.

When connecting my UUT - i've realised that the write Parameter type/ASCII string needs to be send with the following format so that the UUT accepts it as byte hex code. --> "\x01\x04\x30\xCA"

The hex byte string i expect from the UUT as protocol responce is (Hex dislay in vi = 010D 3050 FFFF FFFF 0300 1500 59).

How do i convert the received ASCII string which i am receiving to a hex-byte code representation  i.e. "\x01\x0D\x30\x50\xFF\xFF\xFF\xFF\x03\x00\x15\x00\x59"  ?

thanks in advance

Kech