- NimBLE-Arduino 2.5.1, BLE work in a background task on core 0 - LVGL 9 UI for the round screen: device list (OBD-like devices in green), tap to list services/characteristics, ELM test (ATZ/ATE0/ATI/ATRV/0100) - results saved to LittleFS /ble_log.txt; serial d/c/s commands - shared lv_conf: Montserrat 16 and 20 enabled Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
30 lines
1.5 KiB
Markdown
30 lines
1.5 KiB
Markdown
# BLE Scanner (JC3636W518)
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Stand-alone BLE scanner with on-screen UI, made to find out how the user's ELM327 ("ELM327 Mini V2.1 Dual Mode 5.1") talks over BLE.
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Uses the shared board library and LVGL 9.6 (`../shared`), NimBLE-Arduino 2.5.1.
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## On the device
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1. **Scan screen** — live list of BLE devices: name, MAC, signal (dBm). Devices that look like an OBD adapter (name contains OBD/ELM/VLINK/…, or advertises service FFF0/FFE0/18F0) are shown in **green** with `OBD?`. `(nc)` = not connectable.
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- **Pause / Scan** — stop/resume scanning. **Save** — write the current list to flash.
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2. **Tap a device** — connects and lists all services and characteristics with their properties
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(`R` read, `W` write, `WnR` write without response, `N` notify, `I` indicate).
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If a service has a notify + write pair (ELM-style UART), it is shown as **ELM candidate** and **ELM test** becomes active.
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3. **ELM test** — sends `ATZ`, `ATE0`, `ATI`, `ATRV` (battery voltage) and `0100` (supported PIDs, needs ignition on) and shows the replies.
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4. **Back** — disconnect and return to scanning.
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Every inspect and ELM test is saved automatically (together with the scan list) to `/ble_log.txt` in internal flash (LittleFS, ~900 KB).
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## Reading the results later (USB, serial 115200)
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Send a single character:
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- `d` — dump `/ble_log.txt`
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- `c` — clear the log
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- `s` — print the current device list
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e.g. `pio device monitor` in this folder, then type `d`.
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## Build / flash
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```
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pio run -t upload
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```
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Note: the ELM327 is only powered when plugged into the car's OBD port.
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