import pyvisa
import time

timedelta = 0.02

class BK_9174B:
    
    def __init__(self,adress):
        #establish connection to device with pyvisa. The device is initiallized with visa adress "adress"
        self.rm = pyvisa.ResourceManager()
        try:
            self.inst = self.rm.open_resource(adress, baud_rate=57600)  #Default baud_rate is 9600 but this results in an error.
        except:
            print(f'could not connect to {adress}')
            return
        time.sleep(1)
        
    def __del__(self):
        self.rm.close()
    
    def read_Voltage(self):
        #reads applied voltage of both channels simultaneously. Output has format [V1, V2].

        command1 = f':MEAS:VOLT?'
        command2 = f':MEAS:VOLT 2?'
        data1 = str(self.inst.query(command1))
        time.sleep(timedelta)
        data2 = str(self.inst.query(command2))
        data = [float(data1), float(data2)]
        time.sleep(timedelta)
        return data

    def read_Current(self):
        #reads applied current of both channels simultaneously. Output has format [I1, I2].

        command1 = f':MEAS:CURR?'
        command2 = f':MEAS:CURR 2?'
        data1 = str(self.inst.query(command1))
        time.sleep(timedelta)
        data2 = str(self.inst.query(command2))
        data = [float(data1), float(data2)]
        time.sleep(timedelta)
        return data
    
    def set_Voltage(self, CH, Voltage):
        #sets Voltage in Volt for channel CH

        if CH==1:
            command = f':VOLT {Voltage}'
            self.inst.write(command)
            time.sleep(timedelta)
        
        if CH==2:
            command = f':VOLT2 {Voltage}'
            self.inst.write(command)
            time.sleep(timedelta)
        
    
    def set_Current(self, CH, Current):
        #sets Current in Ampere for channel CH

        if CH==1:
            command = f':CURR {Current}'
            self.inst.write(command)
            time.sleep(timedelta)
        
        if CH==2:
            command = f':CURR2 {Current}'
            self.inst.write(command)
            time.sleep(timedelta)
    
    def set_Output(self, CH, On):
        #sets Output of channel CH on or off. 
        # ON = True -> Turns output on
        # ON = False -> Turns output off

        if CH==1:
            if On == True:
                command = ':OUT ON'
                self.inst.write(command)
            elif On == False:
                command = ':OUT OFF'
                self.inst.write(command)

        if CH==2:
            if On == True:
                command = ':OUT2 ON'
                self.inst.write(command)
            elif On == False:
                command = ':OUT2 OFF'
                self.inst.write(command)
        
        time.sleep(timedelta)
    
    def set_Voltage_slewrate(self, CH, slewrate):
        #sets slew rate of channel CH, [slewrate] = V/ms

        if CH==1:
            command = f':OUT:SR:VOLT {slewrate}'
            self.inst.write(command)
            time.sleep(timedelta)
        
        if CH==2:
            command = f':OUT:SR:VOLT2 {slewrate}'
            self.inst.write(command)
            time.sleep(timedelta)