python Class for communicating Rigol Dp832 programmable power supply

Rigol_DP_832.py

# -*- coding: utf-8 -*-
"""
Created on Sat Dec 21 13:57:32 2013

@author: bjuluri
Uses Pyvisa for commounication
"""
from visa import *
import time, sys


class Rigoldp832():
    def __init__(self, usb_serial):
        try:
            self.instrument_list = get_instruments_list()
            self.usb_address = [elem for elem in self.instrument_list if (elem.find('USB') != -1 and elem.find(
                usb_serial) != -1)]  # Search a instrument with USB and serial number in the instrument list

            if self.usb_address == [] :
                self.status = "Not Connected"
            elif self.usb_address != []:
                self.s = instrument(self.usb_address[0])
                self.status = "Connected"
                self.connected_with = 'USB'
        except VisaIOError:
            self.status = "Not Connected"
            print "Pyvisa is not able to find the connections"


    def mywrite(self, message):
        self.s.write(message)
        time.sleep(0.1)
        error = self.s.ask('SYST:ERR?')
        if error[0]:
            print message+' recieved. No error occured'
        else :
            print message+' recieved. An Error occured: '+ str(error)

    def reset(self):
        """resets the instrument, registers,buffers"""
        self.mywrite("*RST")
        time.sleep(0.2)


    def close_instrument(self):
        self.s.close()

    def set_bias(self, channel=1, i=0.1, i_protection_level=0.1, v=0.5):
        self.mywrite(':INST CH{channel}'.format(channel=int(channel)))
        self.mywrite(':CURR {i}'.format(i = i))
        self.mywrite(':CURR:PROT {i_level}'.format(i_level = i_protection_level))
        self.mywrite(':CURR:PROT:STAT ON')
        self.mywrite(':VOLT {0}'.format(v))


    def turn_off(self, channel = 1):
        self.mywrite(':OUTP CH{channel},OFF'.format(channel = channel))

    def turn_on(self, channel = 1):
        self.mywrite(':OUTP CH{channel},ON'.format(channel = channel))

    def console(self):
        """
        opens a console to send commands. See the commands in the user manual.

        """
        cmd = ''
        while cmd != 'exit()':
            cmd = raw_input('Rigol DP832 console, Type exit() to leave> ')
            if cmd.find('?') >= 0:
                answer = self.s.ask(cmd)
                print answer
            elif cmd.find('?') < 0 and cmd != 'exit()':
                self.s.write(cmd)
        else:
            print "Exiting the Rigol DP832 console"


if __name__ == "__main__":
    r = Rigoldp832(usb_serial='your_Serial_number')
    
	#To start a console
	#r.console()
    
	# This will reset the instrument, apply a bias of 1 V wih 0.1A of protection current for 10 sec and then turn off
    r.reset()
    r.set_bias(channel=1, i=0.1, i_protection_level=0.2, v=1)
    r.turn_on(channel=1)
    time.sleep(10)
    r.turn_off(channel=1)
    r.close_instrument()