test for -1

python/voltcurrent.py

@@ -62,6 +62,7 @@ if __name__ == "__main__":
 #    print("Reading INA219 in MoPower Board")
 #    ina219_one = INA219(I2C(1), 0x4a) 
 #  else:
+  if (buses[0] != -1):
     try:
       i2c_one = I2C(buses[0])
       try:
@@ -99,6 +100,7 @@ if __name__ == "__main__":
     except:
       print("Python Error 5",  file=sys.stderr, flush=True)
       
+  if (buses[1] != -1):
     try:
       i2c_two = I2C(buses[1])
       print(i2c_two)