Phase 5 — Fix parse¶
Parse GGA/RMC (and friends) into fix state, sats, HDOP, lat/lon. Still serial-only — TFT comes next. No new wires.
flowchart LR
NMEA[NMEA stream] --> Parser
Parser --> Lines["FIX / sats / HDOP / lat lon"]
Lines -->|115200| USB[ttyUSB0]Firmware¶
Changed. New folder firmware/05-fix-parse/. Leave earlier phase folders untouched. Same UART2 RX=16 TX=17 baud 9600.
Preconditions¶
- Checkpoint 4 passed (raw NMEA visible)
- Phases 2–4 wiring still on
5.1 Flash¶
Stop any serial monitor on the port first. Check which /dev/ttyUSB* is up.
ls /dev/ttyUSB*
cd firmware/05-fix-parse
pio run -e esp32dev -t upload --upload-port /dev/ttyUSB0
/dev/ttyUSB0
Processing esp32dev (platform: espressif32; board: esp32dev; framework: arduino)
--------------------------------------------------------------------------------
Verbose mode can be enabled via `-v, --verbose` option
CONFIGURATION: https://docs.platformio.org/page/boards/espressif32/esp32dev.html
PLATFORM: Espressif 32 (55.3.39) > Espressif ESP32 Dev Module
HARDWARE: ESP32 240MHz, 320KB RAM, 4MB Flash
DEBUG: Current (cmsis-dap) External (cmsis-dap, esp-bridge, esp-prog, esp-prog-2, iot-bus-jtag, jlink, minimodule, olimex-arm-usb-ocd, olimex-arm-usb-ocd-h, olimex-arm-usb-tiny-h, olimex-jtag-tiny, tumpa)
PACKAGES:
- contrib-piohome @ 3.4.4
- framework-arduinoespressif32 @ 3.3.9
- framework-arduinoespressif32-libs @ 5.5.4+sha.735507283d
- tool-esptoolpy @ 5.3.0
- tool-xtensa-esp-elf-gdb @ 17.1.0+20260402
- toolchain-xtensa-esp-elf @ 14.2.0+20260121
LDF: Library Dependency Finder -> https://bit.ly/configure-pio-ldf
LDF Modes: Finder ~ chain, Compatibility ~ soft
Found 43 compatible libraries
Scanning dependencies...
No dependencies
Building in release mode
Retrieving maximum program size .pio/build/esp32dev/firmware.elf
Checking size .pio/build/esp32dev/firmware.elf
Advanced Memory Usage is available via "PlatformIO Home > Project Inspect"
RAM: [= ] 6.8% (used 22348 bytes from 327680 bytes)
Flash: [== ] 22.7% (used 297440 bytes from 1310720 bytes)
Configuring upload protocol...
AVAILABLE: cmsis-dap, esp-bridge, esp-prog, esp-prog-2, espota, esptool, iot-bus-jtag, jlink, minimodule, olimex-arm-usb-ocd, olimex-arm-usb-ocd-h, olimex-arm-usb-tiny-h, olimex-jtag-tiny, tumpa
CURRENT: upload_protocol = esptool
Looking for upload port...
Uploading .pio/build/esp32dev/firmware.bin
esptool v5.3.0
Serial port /dev/ttyUSB0:
Connecting....
Connected to ESP32 on /dev/ttyUSB0:
Chip type: ESP32-D0WD-V3 (revision v3.1)
Features: Wi-Fi, BT, Dual Core + LP Core, 240MHz, Vref calibration in eFuse, Coding Scheme None
Crystal frequency: 40MHz
MAC: 8c:94:df:6d:c9:5c
Uploading stub flasher...
Running stub flasher...
Stub flasher running.
Changing baud rate to 460800...
Changed.
Configuring flash size...
Auto-detected flash size: 4MB
Writing '/home/johna/workspace/jajera/esp32-gnss-field/firmware/05-fix-parse/.pio/build/esp32dev/bootloader.bin' at 0x00001000...
SHA digest in image updated.
Flash will be erased from 0x00001000 to 0x00006fff...
Compressed 23552 bytes to 15127...
Writing at 0x00001000 [░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░] 0.0% 0/15127 bytes...
Writing at 0x00006c00 [██████████████████████████████] 100.0% 15127/15127 bytes...
Wrote 23552 bytes (15127 compressed) at 0x00001000 in 0.7 seconds (254.9 kbit/s).
Verifying written data...
Hash of data verified.
Writing '/home/johna/workspace/jajera/esp32-gnss-field/firmware/05-fix-parse/.pio/build/esp32dev/partitions.bin' at 0x00008000...
Flash will be erased from 0x00008000 to 0x00008fff...
Compressed 3072 bytes to 146...
Writing at 0x00008000 [░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░] 0.0% 0/146 bytes...
Writing at 0x00008c00 [██████████████████████████████] 100.0% 146/146 bytes...
Wrote 3072 bytes (146 compressed) at 0x00008000 in 0.1 seconds (365.1 kbit/s).
Verifying written data...
Hash of data verified.
Writing '/home/johna/.platformio/packages/framework-arduinoespressif32/tools/partitions/boot_app0.bin' at 0x0000e000...
Flash will be erased from 0x0000e000 to 0x0000ffff...
Compressed 8192 bytes to 47...
Writing at 0x0000e000 [░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░] 0.0% 0/47 bytes...
Writing at 0x00010000 [██████████████████████████████] 100.0% 47/47 bytes...
Wrote 8192 bytes (47 compressed) at 0x0000e000 in 0.1 seconds (474.1 kbit/s).
Verifying written data...
Hash of data verified.
Writing '.pio/build/esp32dev/firmware.bin' at 0x00010000...
Flash will be erased from 0x00010000 to 0x00058fff...
Compressed 297840 bytes to 164422...
Writing at 0x00010000 [░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░] 0.0% 0/164422 bytes...
...
Writing at 0x00058b70 [██████████████████████████████] 100.0% 164422/164422 bytes...
Wrote 297840 bytes (164422 compressed) at 0x00010000 in 4.3 seconds (548.1 kbit/s).
Verifying written data...
Hash of data verified.
Hard resetting via RTS pin...
========================= [SUCCESS] Took 14.42 seconds =========================
pio device monitor -b 115200 --port /dev/ttyUSB0
--- Terminal on /dev/ttyUSB0 | 115200 8-N-1
--- Available filters and text transformations: debug, default, direct, esp32_exception_decoder, hexlify, log2file, nocontrol, printable, send_on_enter, time
--- More details at https://bit.ly/pio-monitor-filters
--- Quit: Ctrl+C | Menu: Ctrl+T | Help: Ctrl+T followed by Ctrl+H
gnss-field fix-parse — phase 5
UART2 RX=16 TX=17 baud=9600
fix=NONE sats=0/0 hdop=99.9 lat=0.000000 lon=0.000000 spd=0.0 utc=
fix=NONE sats=0/0 hdop=25.5 lat=0.000000 lon=0.000000 spd=0.0 utc=
fix=NONE sats=0/0 hdop=25.5 lat=0.000000 lon=0.000000 spd=0.0 utc=
fix=NONE sats=0/0 hdop=25.5 lat=0.000000 lon=0.000000 spd=0.0 utc=
fix=NONE sats=0/0 hdop=25.5 lat=0.000000 lon=0.000000 spd=0.0 utc=
fix=NONE sats=0/0 hdop=25.5 lat=0.000000 lon=0.000000 spd=0.0 utc=
fix=NONE sats=0/0 hdop=25.5 lat=0.000000 lon=0.000000 spd=0.0 utc=
Print ~1 Hz. Indoors fix=NONE with lat/lon zero is normal (matches Phase 4 empty GGA). Window or outdoors for 2D / 3D and real coordinates.
Checkpoint 5¶
- [x] Structured fix lines on serial (even if
NONEindoors) - [ ] Outdoors or window: fix advances toward 3D when sky is open (deferred — fair sky later)
- [x] Logged in Lab log
Next: Phase 6 — TFT fill