# Module of functions to access the TDS 1012B using visa32.dll and PyVisa

from visa import *
from string import *

def FindScope() :
    a = get_instruments_list()
    for b in a :
        if b.find('USB') > -1 :
            h = instrument(b)
    return h    # Return the handle

def ClearQueue(h) :
    h.write('*esr?')
    return h.read()

def SetChannel(h, c) :
    h.write('data:source ch'+str(c))

class ScalingParameters :
    def __init__(self, h, c):
        # c = channel, a number
        # h = the scope
        # assume x increment is in seconds
        h.write('wfmpre:xunit?')
        self.xunit = h.read()
        h.write('wfmpre:xincr?')
        self.xinc = float(h.read())
        h.write('wfmpre:yunit?')
        self.yunit = h.read()
        h.write('wfmpre:ymult?')
        self.ymult = float(h.read())
        h.write('wfmpre:yoff?')
        self.yoff = float(h.read())
        h.write('wfmpre:yzero?')
        self.yzero = float(h.read())


def GetWaveform(h, mode) :
    # mode is ascii or bin
    error = ''
    if lower(mode).find('asc') > -1 :
        h.write('data:encdg ascii')
    else :
        error = 'Only ascii mode is supported.'
        return error, []
    h.write('curve?')
    return error, h.read().split(',')

def FunctionsTest():
    print FindScope()
        
#  Execute
if __name__ == '__main__':
    FunctionsTest()