When I used I2C bus 1 (instead of default 0) and pins P10 + P11, I got the I2C bus to work. I've have the impression that I2C bus 0 and pins P9 + P10 might be reserved or something like this. Can anyone confirm if they're used by UART or button on Expansion board or something like this?
Does anyone know, if 10x orange led blink on Expansion board is some error message? I did not find anything related to this while searching.
@eric73 thanks again. Indeed I was expecting like a popup or message or anything. I just did bluetooth.connect(mac_addr) ad if connected, print something. And it turns out to that the connection was indeed established but silently yes.
if you use the pycom firmware tool and select "development" in the type dropdown on the communication page instead of "stable" you'll flash the latest release candidate that should have a fix for this.
@johncaipa The maximum range of the ADC when using the 11db attenuation is 0-~3V. A Li-Battery has a voltage of up to 4.2V. So you need a voltage divider. And then it does not matter, whether the range at its output is 0-1V or 0-3.3V. So take a resistor pair of 1MOhm(to battery) and 220kOhm, dividing by 5.4545, and use the basic range. Add a smal capacitor at the ADC input to GND to have a low impedance for the moment of sampling. That divider will draw a constant current of 2.5µA. If that is too much, you'll need a P-Mosfet to switch of the divider when not needed.
@juan_peroza JSON is not a protocol, it’s just a data representation. You can send whatever you want, but JSON is not very space efficient, and is usually not the best choice for data sent over a (very) low bandwidth link such as LoRa, SigFox, NB-IoT, or BLE. It’s usually better to use an optimised binary format in those cases.
@giorgio Hi, I've not worked before with the EB3, but I think you should use the Deep Sleep API (https://docs.pycom.io/datasheets/boards/deepsleep/api.html), which may sends messages to the PIC in expansion board to take control of the low power mode, in a similar way as the PySense API does. Also power the board with a LiPo battery.
As the EB3 doesn't have an accelerometer, you should be able to wakeup the SiPy either via an external interrupt, on-board button or timer. Hope this was useful for you.
@calvinblock44 Sigfox enforces that the devices that consume their service need to be registered manufacturers, the Pycom's Sigfox native library contains sensitive information and code that need to be packed and secured (As more as possible). From there you have two options, construct your wifi sniffing functionality over the official firmware or select a more appropriate hardware that fit your needs.
Be aware also that if you are planning to create a final product using certified boards your are not allowed to modify the RF code because is highly possible to void the certification if the code modify the way of signal emission.
This float , have been packed in a binary form
'''s.send(struct.pack('f',float(latitude)) + struct.pack('f',float(longitude)))'''
then sent to sigfox backend data and showed in hexadecimal
so, to have original value you just have to unpack it from hexadecimal to float
''' lat=b'\xd5\x03\x4f\x42' '''this is the way to create and assign hexadecimal value to a 'python byte object' with len=4