Woks from Atom RUN but not when uploaded

[maxi]

Hi forum,
I'm new and I'm testing for a research project a monitoring solution based on LoPy. So fa I have added two DS18B20 to the LoPy + PySense. The strage things is that when i run the code from the Pymkr in Atom it correctly read the DS18B20 temperatures, but when I upload the code on the LoPy the reading is None.

Doe anyone have any idea or similar experience? Where should I look to start debugging?

import time
from lib.onewire import DS18X20
from lib.onewire import OneWire

ow1 = OneWire(Pin('P4'))
ow2 = OneWire(Pin('P8'))
time.sleep(1)
temp1 = DS18X20(ow1)
temp2 = DS18X20(ow2)
while True:

    print("T1:",temp1.read_temp_async(temp1.roms[0]))
    time.sleep(1)
    temp1.start_conversion()
    time.sleep(1)

    print("T2:", temp2.read_temp_async())
    time.sleep(1)
    temp2.start_conversion()
    time.sleep(1)

[maxi]

It looks like it needs a double scan to find the rom.

After inserting

ow1 = OneWire(Pin('P4'))
print('found devices:', ow1.scan())

Even if the print is an empty array ('found devices:[]') then the temperature reading is working with appropriate rom...

Anyone can get why?

Maxi