LabJackSupport

Our DAQFactory for LJM page is chock full of nuggets so I would go through it thouroughly, and take a good look at the LJM_Basic.ctl example that demonstrates many key things. Per AzeoTech's point about using a DF Channel you can find info here: http://labjack.com/support/software/examples/ljm/daqfactory#LinkingChannels Per AzeoTech's point about DF taking care of Handle, the following hints at that: http://labjack.com/support/software/examples/ljm/daqfactory#Opening ... and then does not seem to be clearly stated, but you can see the example script is passing an LJM identifier as the first parameter: http://labjack.com/support/software/examples/ljm/daqfactory#Script

See "Opening a Device" here: https://labjack.com/support/software/examples/ljm/daqfactory DAQFactory's D# is the Identifier parameter passed to the open call: https://labjack.com/support/software/api/ljm/function-reference/ljmopens "To specify an identifier, use a serial number, IP address, or device name." With USB, serial number would be the common choice to pass.

The modbus write function is documented here: https://labjack.com/support/datasheets/t-series/scripting/labjack-library I don't spot anything wrong in your calls to set FIO0 to output-high and output-low. Check out the Lua example "Toggle DIO 1Hz". We can continue troubleshooting that, but my approach might be a little different. How about using USER_RAM0_U16 and having the Lua script increment it when desired. Then DAQFactory can read that register and note if it has changed from the previous value. That way you never miss a trigger. https://labjack.com/support/datasheets/t-series/lua-scripting

To talk to an EI-1050 through a U3 requires special function calls as described in "UD Library Communication" here: https://labjack.com/support/datasheets/accessories/ei-1050 Have you tried "EI1050 U3.ctl"? https://labjack.com/support/software/examples/ud/daqfactory

The comment you are seeing in LabJack forum topic is about directly controlling a solid-state relay (SSR), which is best done using "sinking" control. When you do that you need to change the DIO between input (relay off) and output-low (relay-on). https://labjack.com/support/app-notes/Controlling-Relays With the RB12, however, you just change the DIO between output-high (module off) and output-low (module on). The following is from the RB12 Datasheet: "The RB12 behaves with inverted or negative logic. For output modules that means the applicable LabJack DIO must be set to output-low to enable the I/O module. Output modules will be disabled with the DIO set to input or output-high." https://labjack.com/support/datasheets/accessories/rb12