GPS

Open from: main menu e → Grove 4 / g

AT6668 NMEA 0183 (~115200). Two hardware sources; on enter the App auto-detects (Cap first, then Grove):

Source	Hardware	Host UART	Notes
Cap LoRa	Cap LoRa-1262 built-in GNSS (ATGM336H @ AT6668)	RX=G15 / TX=G13	Does not take left Grove I2C; Radio / NFC stay usable on Adv + Cap
Grove	GPS Unit (AT6668) or compatible UART NMEA	RX=G1 / TX=G2	Ex_I2C.release() on enter; I2C restored on leave

Settings shows the active source read-only (Cap LoRa G15/G13 / Grove G1/G2 / none). Probe waits ~1 s for $; if neither answers, Grove stays open so a slow-starting unit can still come up (then labeled Grove).

Cold start (power loss or long idle) takes about 20+ seconds to acquire satellites; hot start (recent fix) is about 1 second. Clear outdoor sky is faster; indoors you often stay on NO FIX.

Screenshots

Empty (NO FIX / before acquire)

With fix (3D FIX)

Chart: Speed / Alt / Accel / All / Map

Module & wiring

Grove GPS Unit

Use an M5Stack GPS Unit (AT6668) or a compatible UART NMEA module on the left Grove (HY2.0-4P). This path is not I2C — the same pins run as serial:

Grove pin	Role (GPS)
GND	Ground
5V	Power
G2	TX (module → host RX)
G1	RX (host TX → module)

Baud 115200. With the Grove source, do not share the left Grove with Radio / NFC at the same time.

Cap LoRa-1262 GNSS

On Cardputer-Adv, attach Cap LoRa-1262 (built-in ceramic GNSS antenna). UART matches the official Arduino sample: Serial1 RX=15 / TX=13. This App uses GNSS only (no SX1262 LoRa init). The Cap HY2.0-4P can still host other Grove I2C devices.

Pages

Key	Page	Content
1	Live	Speed, lat/lon/alt, HDOP, sats, course, UTC
2 / s	Speed	Trip stats, 0–50 / 0–100, braking, peak g
3	Satellites	GPS / BeiDou / GLONASS / Galileo / QZSS + PDOP/VDOP
4	Sky plot	Sky map (north-up) + SNR list
5 / l	History	Saved runs; Enter opens chart, Bk deletes
6 / o	Settings	Active source (read-only) + rate 1 / 2 / 5 / 10 Hz (PCAS02, NVS)

Header right: NO FIX / 2D FIX / 3D FIX; while recording a stop icon blinks.

Shortcuts

Full list: h Help (multi-page).

Key	Action
h	Help
1–6 / s l o	Switch pages (table above)
Space / BtnGO	Start / stop speed recording
r	Reset Live / Speed stats (restarts record if active)
m	On chart: cycle Speed / Alt / Accel / All / Map
↑ ↓ etc.	Select history row or settings rate
Enter	History → chart; Settings apply rate
Bk	Delete selected history
ESC	Chart → History; Settings → previous page; Help → close

Fields

Field	Meaning
Lat / Lon / Alt	Latitude / longitude / altitude (m)
HDOP / PDOP / VDOP	Dilution of precision (lower is better)
Sats	Used / visible satellites
Course	Heading (degrees)
0–30 / 0–50 / 0–100	Time to reach that speed
100–0	Brake time from 100 km/h
Accel	Peak accel / brake (g)

Sky plot: rings are elev 0° / 30° / 60°; dots G/C/R/E/J by system, size by SNR.

Usage

1. Plug a Grove GPS Unit, or use Adv + Cap LoRa-1262; main menu e → g (or 4).
2. Open Settings (o) to confirm the source; wait outdoors for 3D FIX (cold ~20+ s, hot ~1 s).
3. Space / side button starts a run; press again to stop and save to History.
4. Update rate often ships at 1 Hz; max 10 Hz uses more power.
5. Leaving the App stops recording and ends UART; Grove I2C is restored if that source was used.

Records & route

• On History chart, m cycles Speed / Alt / Accel / All / Map (lat/lon path on the left, summary on the right).
• Import / export: open Config Web → GPS (/gps). Format is GPX 1.1 (universal for map apps); sprint peaks, fused speed, accel, sats, etc. live in cardputer: extensions for a full round-trip. Importing when 12 runs are full drops the oldest.