EmStat Pico - Simultaneous Separate Tests

Hi there!

Is it possible to run two separate tests simultaneously?  For example, I'd want to run an OCP test on Channel 0 and a CA test on Channel 1 at the same time.

The "poly_we" function will not work because we need the Channel 0 OCP test to use the WE0, RE0, and CE0 inputs -- while the Channel 1 CA test must use the WE1, RE1, and CE1 inputs.

In the MethodSCRIPT v1.2 PDF, the "11.44 set_pgstat_chan" function seems to indicate that the parallel channel feature will be available in the future.  I believe this would suit our needs, would you agree?  When will this feature be available?

Thank you!

  • Hi nmcgillbg,

    Your conclusion that the "poly_we" command is not suitable for your purpose is correct. It is meant to be used when you just want to add an extra WE to the same experiment.

    It is already possible to use two channels somewhat parallel to each other, provided both channels use the low speed mode. Note that this will only work if the sensors do not share any electronical connection. Both channels are able to be configured independently and these settings will still be applied even when the channel is not selected. However, the "meas_loop_*" commands cannot run a technique on two channels at a time. You can, however, switch to a separate channel and sample an electrode using the "meas" command.

    Note that the two measurements will be offset from each other in time, as the EmStat Pico you can only sample one value at a time. But you will be able to measure both channels in one iteration.

    In the case of your CA that also does an OCP channel, the MethodSCRIPT would look something like this:

    e
    var c
    var p
    var t
    #init OCP channel (keep cell off)
    set_pgstat_chan 0
    set_pgstat_mode 2
    set_max_bandwidth 40
    set_pot_range 300m 300m
    set_cr 590u
    set_autoranging 590u 590u
    #init CA channel
    set_pgstat_chan 1
    set_pgstat_mode 2
    set_max_bandwidth 40
    set_pot_range 300m 300m
    set_cr 590u
    set_autoranging 59n 590u
    cell_on
    timer_start
    #Pick CA as measurement, we can measure CH1 OCP inside the meas_loop_ca
    #potential(V[out]), current(A[out]), potential setpoint (V[in]), interval (s[in]), total runtime (s[in])
    meas_loop_ca p c 300m 100m 120100m
        #measure OCP on channel 0
        set_pgstat_chan 0
        #measure potential(ab) for 25m and put result in p
        meas 25m p ab
        #switch back to chan 1 for next iteration
        set_pgstat_chan 1
        timer_get t
        pck_start
        pck_add t
        pck_add c
        pck_end
    endloop
    on_finished:
    cell_off
    
    

    I don't expect we will be able to implement parallel measurement loops in the near future.

    Kind regards,

    Hielke

  • Thank you Hielke!  This seems like a great short term solution for me.