Executing "TriggerList" using GPIB Interactive Control

Hi all,

For debugging purposes, I am trying to execute a multi-device "TriggerList" command using the "GPIB interactive control" utility.

I have a GPIB-USB-HS unit connected to 2 GPIB devices at addresses 11 and 12. Communication to these devices seperately works fine.

What I tried so far:

(1) Opened NI-MAX, browsed to "Devices and Interfaces" / "GPIB-USB-HS "GPIB0";

(2) Pressed the 'interactive control' button, which opens up the GPIB Interactive Control terminal window, with a "gpib0:" prompt;

(3) Enter "TriggerList 11,12" and press enter.

the result of this is:

[8000] (err)

error: EHDL

count: 0

Using the "NI I/O Trace" tool, I see that a TriggerList(31000, {0x000B, 0x000C}) call is executed, and returns with an EHDL error.

My question: what am I doing wrong, and what do I need to do to execute a successful TriggerList?