How do I initial another TX/RX port on Gpy board mounted on Pytrack2.0



  • Hi,

    I have a Gpy mounted on Pytrack2.0 aiming to use the GPS and accelerometer functions. Right now I wish to add other I2C and serial devices so that I can have my sensor package as a whole. I got a few questions that I hope any of the professionals can help.

    1: Referring from Pytrack2 spec sheet, sockets 7/8/9 on left and sockets 7/8/9/10/11/12 on right are reserved (not been used my understanding). Does this mean I can use right pins 7/8 (P20/P19) on Gpy as other serial pins (TX/RX)? Can all the reserved socket be used for other purposes (sockets 7/8/9 on left are not available since they are connected to Gpy LTE module)?

    Pytrack2.0 pinout
    b3890c7e-25f1-40bd-a13e-84d578dce54a-image.png
    Gpy pinout
    a9a7b914-38f1-4b28-a9cd-4e38ea195ac4-image.png

    2: I also noticed that GPS and accelerometer modules are using Pytrack right socket pin5/6 (P22/P21) for SDA and SCL. Does this mean I cannot use Gpy DAC pins (P22/P21)?



  • @Gijs I encountered some strange behaviour on my FiPy+PyTrack2 combination when adding another I2C bus in the system. Noted that P-numbers refer here is what we use in micropython (eg. 'P12')

    • FiPy could not get the slave address if the bus 1 assigned as P10(SDA), P11(SCL)

    • FiPy able to return the correct slave address if bus 1 assigned either with combo 1. P9(SDA), P10(SCL) or combo 2. P9(SDA), P11(SCL)

    My code example,
    Screen Shot 2020-11-11 at 2.04.48 PM.png

    This is rather odd to me, as the additional I2C only work with P9+P10, or P9+P11 combination. Is anybody encounter the similar behaviour before? Appreciate for your time and reply.

    thanks,
    elaine


  • Global Moderator

    Sorry, that could be my mistake, I might have been confused by the many pin naming conventions around..

    You should be able to remap the UART pins to those I believe (note that P15 is only input if Im correct)

    Gijs



  • @Gijs said in How do I initial another TX/RX port on Gpy board mounted on Pytrack2.0:

    And the other pins you mention (P15 - 20) are also not connected on the Pytrack

    Hi @Gijs, I have checked the connectivity on P15 at Pytrack2. It does connect on Pytrack2, to "Sensor Header" pin6, labelled as GP0. May I check if this GP0 reserve for any default function on Pytrack2 "Sensor Header"? can I remapped this P15 as UART1 Rx? and pin5 on "Sensor Header"/EXT_IO_1/P9 as UART1 Tx?



  • This post is deleted!

  • Global Moderator

    Hi,

    Sorry if I was unclear. The pins you mention are not connected to anything on the Pytrack, but let me explain further:

    The external IO on the header are connected as follows (you are correct, the order is indeed wrong in the figure, I will get that updated!)
    EXT_IO0 --> P2 / ICSPDAT
    EXT_IO1 --> P9 / ICSPCLK
    EXT_IO2 --> P10
    EXT_IO3 --> P11
    EXT_IO4 --> P4 / SD_CMD
    EXT_IO4 --> P8/ SD_DAT

    Then P5-7 are not available (LTE modem)

    where the P-numbers refer to what you can use in micropython (eg. 'P12')

    And the other pins you mention (P15 - 20) are also not connected on the Pytrack

    Best,
    Gijs



  • @soopieng Yes, I think this is what he meant.
    I haven't tried to use those pins yet. But once I got a chance to try, I will post my results.



  • @Gijs said in How do I initial another TX/RX port on Gpy board mounted on Pytrack2.0:

    Hi @Gijs, when you said pin7-12, did you mean the socket pin at table 3?

    Pins 7-12 are not connected to anything (from what I can see in the schematic) so they should be free to use! Sorry for the misunderstanding. To be honest I expected the IO header to have more functionality than it does..


  • Global Moderator

    Hi,
    No problem, that is what Im here for!

    Pins 7-12 are not connected to anything (from what I can see in the schematic) so they should be free to use! Sorry for the misunderstanding. To be honest I expected the IO header to have more functionality than it does..

    Hi not to make new topic. I have GPY and Pysense to what Pins I can add an external GPS chip (UBLOX NEO 6M )that have uart TX/RX and 3.3v. To those G1 and G2 pins ? that ar program port ? It would not interfere. ?

    I want to create gps logger that logs temp and pressure. and instantly send to server using lte -m

    To answer your question, You can use UART1 to connect the external GPS module (P3 and P4). If you connect them to P1 and P2, uploading new programs will probably no longer work as that is handled by the same UART. Though I would recommend the Pytrack 2.0 X with the additional sensor nodes that you can attach to the Pyport (hopefully we will release those soon!)

    Best,
    gijs



  • Hi not to make new topic. I have GPY and Pysense to what Pins I can add an external GPS chip (UBLOX NEO 6M )that have uart TX/RX and 3.3v. To those G1 and G2 pins ? that ar program port ? It would not interfere. ?

    I want to create gps logger that logs temp and pressure. and instantly send to server using lte -m



  • Thank you, Gijs! Seems like you are the person answered most of my recent post! I appreciate it!

    However, seems like, except EXT_IO_3, all other external IO pins have been occupied by PIC chip and Pycom module SD_CMD and SD_DAT. If I use the SD module on the Pytrack2, does this mean Pin 8 and 9 on the external IO header can not be used for other purposes? Also, Pin 11 is a duplicate of Pin 6.
    77de3117-ae1c-4b7a-acff-9acff055eac9-image.png

    Based on Table 3, should I be able to use Gpy P15~P20 (corresponding to sockets 7~12, which said they are reserved) for analog input?
    cd1e3c9f-32df-4532-a4c2-e520d9303c70-image.png


  • Global Moderator

    Hi
    To answer your question

    Can all the reserved socket be used for other purposes (sockets 7/8/9 on left are not available since they are connected to Gpy LTE module)?

    You can use all the pins on the external IO header (for some reason they are not all listed in the figure, but you can find them labelled in the datasheet. Indeed note the LTE modem connections. https://docs.pycom.io/gitbook/assets/PyTrack2X_specsheet.pdf)

    I also noticed that GPS and accelerometer modules are using Pytrack right socket pin5/6 (P22/P21) for SDA and SCL. Does this mean I cannot use Gpy DAC pins (P22/P21)?

    Yes, unfortunately these pins are already reserved for I2C.


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