• Layout documetation, SiPy vs PySense, what is correct

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    robert-hhR
    @PeterB Actually it should read Gxx instead of GPIOxx, where not by chance that matches the old WiPy1 numbers. And yes, this inconsistency has been reported over & over. It should have been fixed.
  • Interference of functions? Pin Wake Up, I2C, SD-Card

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  • High temperature rise with 18650 battery.

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    S
    Thanks jcaron... Polarity was correct coming out of the battery based on the red/black colour of the wires going to the JST connector, but wrong going into the Pycom board...all good now system is working well. Thanks again.
  • Missing some files?

    l76gnss pytrack
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    C
    @aliubi You will find the directory tree on top of the page over the code tab. You can download the whole stuff at once. Click on the green clone or download button on the right side and choose download as zip.
  • 0 Votes
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    M
    @agotsis Primarily you need a voltage supervisor. But as robert also just observed, you should use a hardware watchdog as well (that needs to be periodically retriggered and otherwise generates a hardware reset), so I'd recommend using a device that has both functions. As a side note, this "brownout" condition (supply dropping to 1-2 V - not zero!) and rising again can put many microcontrollers in a hung-up state which can't even be recovered by a hardware reset (!), but needs a power cycle (down to 0 V) to restart the microcontroller. This is pretty nasty, fortunately I have not observed this yet with the ESP32 (nor have I tested it).
  • snr vs distance in lora

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  • snr limits for US 915

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    @jcaron thanks a lot. I had checked out some online webpages and lorawan specification mentioning this data rates.
  • adaptive coding rate

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  • Filename length limitation for SD card?

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  • UK use of Gpy/FiPy

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  • Pyscan firmware update

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  • Data Rate & Throughput

    data
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    K
    As the distance increases, the transmission - reception time increases. This results in increases bit error rate and reduced throughput. The observation made by you is as per expectations.
  • Default SF and Coding Rate ?

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    @snehasg96 Hello, according to documentation https://docs.pycom.io/firmwareapi/pycom/network/lora.html Default contructor setting is SF7 CR=4/5 lora.init(mode, * ,region=LoRa.EU868, frequency=868000000, tx_power=14, bandwidth=LoRa.BW_125KHZ, sf=7, preamble=8, coding_rate=LoRa.CODING_4_5, power_mode=LoRa.ALWAYS_ON, tx_iq=False, rx_iq=False, adr=False, public=True, tx_retries=1, device_class=LoRa.CLASS_A) If by FEC you mean CR, sx1276 (lora-chip) was unable to do less than 4/5.
  • 0 Votes
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    @jcaron We are using the pysense library for it. It could have been the suggestion we read somewhere else on the forum for connecting P8 with a resistor to 3V3. If we remove the resistor it seems to work. More testing being done at the moment.
  • MQTTClient subscriptions not working

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    Well, whatever umqtt.simple works fine. import machine from umqtt.simple import MQTTClient def mqtt_output_command_callback(topic,message): print('sub') print(topic) l99_serial = "abc" mqtt_client = MQTTClient(l99_serial, '192.168.2.107', 1883) mqtt_client.set_last_will('L99/{}/io/state/offline'.format(l99_serial), '', qos=1) mqtt_client.connect() mqtt_client.set_callback(mqtt_output_command_callback) mqtt_client.subscribe('L99/{}/io/OUTPUT/+/+'.format(l99_serial), qos=1) mqtt_client.publish('L99/{}/io/state/online'.format(l99_serial), '', qos=1) while True: machine.idle() mqtt_client.check_msg()```
  • New LTE band support, available from distributors?

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    robert-hhR
    @reidfo my hint may have been wrong. I remember that I could call attach() with band=8, not getting any error, but it simply did not attach. So maybe Paul knows how to get that information from the modem.
  • Pysense charging current

    pysense lipo lipo battery charging
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    @martinnn said in Pysense charging current: @peterb If you look at the PCB, from pin 2 (ISET) of the charger a trace goes directly to a 0402 resistor (which is connected to GND), measuring 1.2 kOhm. Looks pretty obvious to me. Probably difficult to see without microscope though. Thanks! I will find a mircroscope.
  • Security and frozen modules

    secure boot frozen modules repl
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    robert-hhR
    @troy-salt If you have access to the device, you can read the flash with esptool.py.
  • Protection circuit for Analog Pin

    protection analog in 3v3 3.3v
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    @martinnn said in Protection circuit for Analog Pin: How exactly do you suppose this to function? This is what I put into a online simulator. If I change the impedance on the right then I can adjust the trim pot and it changes the working range. [image: 1551398013598-c8ac1f5a-9119-49ea-a614-6e56c948f1a1-image-resized.png] This is a digital input, not an analog one. Re-read what I wrote about input protection. How much current flows into the input? Draw a schematic including the input protection as in the article you are referring to (hint: Figure 6). Do you mean what you wrote when you said to use an input series resistor. Is the circuit above what you meant? EDIT: I have since found out that the impedance will be minimal. It is just the resistance of a short cable. So less than 1 ohm. Also this device will go into deep sleep in which case there will still be the analog but no power to the FiPy. Won't this then apply a voltage to VDD?
  • Wireshark for LoRa?

    wireshark lora protocol header
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