19 lines
2.6 KiB
Markdown
19 lines
2.6 KiB
Markdown
# TFmini Plus distance bench
|
|
|
|
This is a receive-only sketch for a DFRobot DFR1154 ESP32-S3 camera board and the owned TFmini Plus. It **compiles but has not been flashed or run**. It reads the sensor's default 9-byte UART frames, checks the checksum and signal strength, and reports distance and a range-only `near` flag over USB serial. It does not perform person detection or change either eye. The TF-Luna uses the same default frame, but this sketch's 10 cm minimum must be changed to 20 cm before using it with that sensor.
|
|
|
|
Before wiring, confirm the actual camera board revision and sensor cable against the [DFRobot board documentation](https://wiki.dfrobot.com/dfr1154/) and [Benewake TFmini Plus manual](https://en.benewake.com/uploadfiles/2025/04/20250430175221028.pdf). The manual's stock cable lists red +5V, white RXD, green TXD, and black GND. Verify the cable on the unit at hand before applying power. The intended receive-only connection is:
|
|
|
|
| TFmini Plus | DFR1154 bench connection |
|
|
| --- | --- |
|
|
| +5V | Regulated 5 V supply, sized for at least the manual's 140 mA peak |
|
|
| GND | Supply ground joined to DFR1154 ground |
|
|
| TXD | Exposed DFR1154 GPIO44 / RXD (3.3 V UART signal) |
|
|
| RXD | Leave disconnected for this read-only test |
|
|
|
|
Do not use the camera board's 3.3 V pin to supply the TFmini Plus; the manual specifies 5 V ±0.5 V. The sketch assumes the sensor still has its factory UART setting of 115200 baud and 9-byte frames in centimeters. It rejects bad checksums, signal strength below 100 or overexposure, and distances under the 10 cm rated minimum. It reports `near=1` at or below 61 cm and returns to `near=0` at or above 76 cm or after 300 ms without a valid reading. Those thresholds are bench settings; the final effect also needs person confirmation and synchronized messages to both eyes.
|
|
|
|
The compile-only board profile used on this laptop is `esp32:esp32:esp32s3:FlashSize=16M,PSRAM=opi,PartitionScheme=app3M_fat9M_16MB,USBMode=hwcdc,CDCOnBoot=cdc` with Arduino ESP32 core 3.3.5. The build uses 322,359 bytes program storage and 21,360 bytes static RAM. The DFR1154's actual flash/PSRAM and USB configuration must be checked before upload. Uploading this sketch would replace whatever camera firmware is currently installed; save its recovery path first.
|
|
|
|
For a bench run, record the printed distance and strength at approximately 10, 20, 45, 60, and 75 cm, a very-close position, several off-axis positions, and when a nearby object is present without a person. Record observations in `tracking/proximity-bench.md` and decide whether the narrow beam and mounting position are acceptable.
|