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kmartinez / dgpstracker2

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Things to think about further #5

Open yian2k opened 2 years ago

yian2k commented 2 years ago

Need to tackle each issue step-by-step.

Tasks:

  1. Need to make sure the rover is getting fixes from the base, this can be checked using u-center, with both devices configured and having their UARTs (Rx and Tx) connected.
  2. Figure out how to make the rover go past the "calibration" stage in Emily's code, try using both devices/ different wiring to figure out where the problem is.
  3. Figure out how the Xbee radios can communicate and make them send simple byte streams to each other (UART?). The SX 868 radios can communicate with each other, but they receive the data as a byte array instead of an ASCII byte array. It turns out baud rate of 38400 doesn't work well with the radios. 115200 works and we can see proper byte messages on both ends.
  4. Code should be commented properly and commited to the repository, so that further work is easier.
  5. The u-center configuration files for the rover/base should be saved (preferably to the git repo).
  6. At some point the LCD lines of code should be omitted - perhaps will need to see the output (readable) on the REPL using pyboard.
  7. Check where/whether the base station is set to TMODE3 in the code.

Issues:

  1. Apparently the Survey-In method does not always work well (according to the community). Perhaps, it would be a good idea in Iceland to get a good enough fix, e.g. 5m accuracy and then switch to a fixed mode with the best obtained location configured in the code. After that, the TMODE3 can be entered to begin sending out corrections to the rover. When a Survey-In location is obtained that is at least the minimum desired accuracy or a maximum survey-in time has passed, the base goes into TIME mode. The RTK corrections are then sent out through the UART automatically.
  2. The PWR LED (red) on one of the Sparkfun GPS kits doesn't light up on the rover for some reason, something could be wrong with the hardware. Red PWR LED is broken.
  3. In Emily's report, apparently there is an issue with two-way communication. In other words, the base station can only send corrections with Tx, receive log data (location and other outputs from the rover) and communicate that to the user's PC via satellite (SWARM). Perhaps this is an issue with the radios that were used and not with the SX 868s. Needs investigating.
  4. There should be a blue LED lighting on the pyboard when corrections are obtained (comms between two devices). This is not the case so far. Blue LED begins blinking when RTCM messages received and turns off when RTX fix established (on rover).
  5. The base station does not send an ACK to the rover (yet).

Milestones:

sua-dev commented 2 years ago

Didn't we establish communication between the radios using UART in the end? We agreed that the preferred baud rate was 115200 and confirmed communication worked via REPL and PuTTY.

kmartinez commented 2 years ago

radios tested on their own OK with ftdi and terminal - this leads us to stick to 115200 baud for all coms with the radio from the pyb. Remaining test hinted above is using radio back from rover to base...