[Tutor] Connecting Py 2.7 with visa

[Wilson, Pete]

Greetings I am trying to write a test executive program using python 2.7 on a windows 7 computer. I want to connect to  a Keithley 2100 voltmeter using National Instruments VISA. I am having trouble installing pyvisa. All the documentation refers to using 'pip' and a command line "$ pip install pyvisa" . What interface or console is this? "$" prompt looks like a Linux command line. How do we do this with windows?

Do I have to do this? Or can I use the native visa module in Python 2.7? Using the help() and dir() features I can get some basic information about visa, but the functions have changed, like visa.ResourceManager.open_resource is not working. I really liked this function... Are there any examples of how to use this new visa? I have some working code below that uses pyvisa, can it be converted?

def update_current():
    import visa

    rm = visa.ResourceManager()
    rm.list_resources()

    current_1_ma = ""
    exe_check = "PASS"

    try:
        dut_data = open("dut_data.txt", "w")
    except:
        exe_check = "FAIL"

    try:
        ki2100 = rm.open_resource('USB0::0x05E6::0x2100::1148525::INSTR')
        device_id = ki2100.query("*IDN?")
    except:
        exe_check = "FAIL"

    try:
        dut_current_amps = (float(ki2100.query("MEASure:CURRent:DC?")))
        dut_current_ma = dut_current_amps * 1000.0
        current_1_ma = "%6G" % dut_current_ma
    except:
        exe_check = "FAIL"

    new_line = "Litepoint_Data_Format" + "\r\n"
    dut_data.write(new_line)
    new_line = "CURRENT_1_MA=" + current_1_ma + "\r\n"
    dut_data.write(new_line)
    new_line = "EXE_CHECK=" + exe_check + "\r\n"
    dut_data.write(new_line)

    dut_data.close()

    return


if __name__ == "__main__":

    update_current()

    print "Dumping dut_data.txt"

    with open('dut_data.txt') as dut_data:

        for line in dut_data:
            print line,
           if 'str' in line:
                break

    dut_data.close()