address 0x08 in the PIC microcontroller on the Pytrack/sense so it is supposed to be there. When I tested this out on a LoPy4 with the latest firmware and a Pytrack with the latest firmware it worked fine the first time. So are you completely unable to talk to the PIC without errors?

@robert-hh Thanks a lot, Man! Works like a charm. :) Now I get where I was wrong! I was measuring pulses the wrong way. Moreover, I wasn't resetting the self.start variable..!! :'D Thank You, Devang.

try _thread

@ahelllycan Using a serial terminal emulator program like picocom, minicom or screen, you can connect as many devices as you have available USB ports. Just open for each device a terminal window and start the serial terminal using the repective interface. The interfaces are called /dev/ttyUSB0, /dev/ttyUSB1, .... Example: picocom -b 115200 /dev/ttyUSB0 picocom -b 115200 /dev/ttyUSB1 .... To close picocom, enter Ctrl-A Ctrl-X of close the window with picocom.

@sai9959 Hi did you get the solution for this? I am also working on the same. Please share your solution here.

I live in the Netherlands. I am about 1.6 km away from a gateway. The response after joining is: { "time": "2018-01-17T10:17:07.155968027Z", "frequency": 867.3, "modulation": "LORA", "data_rate": "SF7BW125", "coding_rate": "4/5", "gateways": [ { "gtw_id": "eui-008000000000aa8a", "timestamp": 2268423667, "time": "2018-01-17T19:09:11.459706Z", "channel": 4, "rssi": -117, "snr": -3, "latitude": 53.20986, "longitude": 6.54523, "altitude": 15 } ] }

Yes they are, just email sales@pycom.io and they'll sort you out

Hi, I'm also experiencing this exact same problem with a Sipy and expansion board. Has there been any solution/reason to this issue? Using an external GPS but of the same brand type that is on the Pytrack (mine is the l80). Using the same speed and pins as the original poster. Sipy and Expansion board have both been upgraded to the latest firmware.

@chumelnicu Hey, you can look it up here (scroll down) or try to transcribe the Adafruit library

@livius thanks that did the trick

@jmarcelino just as a note. P19 is not working for me as Input. P20 does. I'm now running the latest firmware. This seems to have not changed anything for me at least.

Found the issue. It was actually caused by gc.collect() run time going from 6mS to 48mS. This was being run inside a timer tic ISR (I know, that's a no-no). The ISR was taking longer to run than the timer tic period. I assume the UART Int is a lower priority than the timer so it was never being processed. Is gc.collect() taking so long because of the extra memory or is this a bug?

For completness one might also mention that there are another pins which should be used with care: MTDI / P9 is the ESP strapping pin to select the voltage of the internal LDO. MTDO / P4 is the ESP strapping pin for debug logging during boot GPIO2 / P8 (together with PIO0) is the ESP strapping pin to select boot mode GPIO5 / Sigfox CLK (together with MTDO) is the ESP strapping pin to select SDIO Timing

@gruia-nichita I do not work with the pymakr plugin. It's too obscure for my opinion. You can always copy the file to the board with ftp, using FileZilla or FireFTP. Instructions on how to do that are in the docs: https://docs.pycom.io/chapter/toolsandfeatures/FTP.html

@mikexu007 You can work with same lib