Python NI-DAQ multi-board acquisition

[DiegoBoulder]

I'm using two PCIe 6259 boards connected with an RSTI cable. I'm using the Python NI-DAQmx library to control them. I have used these boards in MATLAB for multi-board acquisition but I keep getting boards can't be used, the error is: "nidaqmx.errors.DaqError: One or more devices do not support multidevice tasks. Device: Dev1 Device: Dev2"

N = 512

sampleRate = 110e3

readTask = daq.Task('readTask') # Create analog read task

readTask.ai_channels.add_ai_voltage_chan('Dev1/ai0', terminal_config=TerminalConfiguration.RSE)

readTask.ai_channels.add_ai_voltage_chan('Dev2/ai0', terminal_config=TerminalConfiguration.RSE)

readTask.timing.cfg_samp_clk_timing(sampleRate, sample_mode=AcquisitionType.CONTINUOUS, samps_per_chan=N)

reader = readTask.in_stream

readTask.start()

attached below is te full script I just want help understanding how to connect the boards. 

[ZYOng]

Did you Registering Your RTSI Cable in MAX?

To create a multi-device route, the source and destination devices must share a trigger bus both physically and logically in MAX. For PCI devices, you must register your RTSI cable in MAX.

See Real-Time System Integration (RTSI) and Configuration Explained

[DiegoBoulder]

I have registered the RTSI cable with MAX. I have done a little more research and found out that PCIe-6259 is an M-class device, so it does not support multi-device tasks. So I'll have to figure out how to synchronize them with separate tasks. So all my code is useless. 

[ZYOng · Accepted solution]

Good catch. In that case, you would need two separate tasks. You can refer to nidaqmx-python/examples/analog_in/ai_multi_task_pxie_ref_clk.py at master