WetterCubePlus/Hardware und Verkabelung/en
Note on assembly: The WetterCubePlus is aimed at people with some knowledge of electronics: during assembly, cables have to be crimped and parts soldered. If you do not want that, the WetterCube Fusion is the better choice. That is why, for the newer devices (Fusion and Next), I rely on complete boards with an integrated display: building is easy even for people who know nothing about wiring up an ESP32 and the like.
Parts
| Component | Type |
|---|---|
| Microcontroller | ESP32-S3 N16R8 (16 MB flash, 8 MB OPI PSRAM) |
| Display | ILI9488, 3.5", 480×320 pixels, SPI ("3.5 TFT SPI 480x320" module) |
| Touch | XPT2046, resistive, separate SPI bus |
| Backlight | PWM via the ESP-IDF LEDC driver, GPIO 17 |
Display (ILI9488), SPI2
| Display pin | ESP32-S3 | Note |
|---|---|---|
| VCC | 3.3 V | not 5 V |
| GND | GND | |
| CS | GPIO 15 | chip select |
| RST | GPIO 16 | reset |
| DC / RS | GPIO 2 | data/command |
| MOSI / SDI | GPIO 13 | SPI data |
| SCK / CLK | GPIO 14 | SPI clock |
| LED / BL | GPIO 17 | backlight (PWM) |
| MISO / SDO | GPIO 12 | optional (read commands only) |
Touch (XPT2046), separate bus SPI3
The module has its own touch pins: T_CLK, T_DIN and T_DO are not connected to the display's SCK, SDI and SDO.
| Touch pin | ESP32-S3 | Note |
|---|---|---|
| T_CLK | GPIO 6 | separate bus |
| T_DIN | GPIO 7 | touch MOSI |
| T_DO | GPIO 8 | touch MISO |
| T_CS | GPIO 21 | chip select |
| T_IRQ | GPIO 18 | not used (touch is polled) |
Power supply
| ESP32-S3 | Connection |
|---|---|
| 5V / VIN | USB or external 5 V |
| 3.3 V | display VCC and touch VCC |
| GND | common ground |
The ESP32-S3 draws short current peaks when transmitting over Wi-Fi, on top of the display and backlight. A power supply of at least 5 V / 2 A and a short, thick USB cable are recommended. A weak supply or cable can cause Wi-Fi failures or a brownout reset at cold start (see Diagnostics and troubleshooting).
Case to print yourself
The case from the photos (lower part and lid, version 2) is available for free as 3MF files: folder gehaeuse/ on GitHub. Outer size according to the file: lower part 108 × 91.4 × 75.8 mm, lid 108 × 66.1 × 66.3 mm (width × depth × height). Recommendation: print in PLA or PETG with a 0.4 mm nozzle. A ready-made print profile on Bambu MakerWorld will follow shortly. Licence of the files: CC BY-NC 4.0.
Notes
- Do not use GPIO 33–37! On the N16R8 they are reserved internally for the OPI PSRAM.
- GPIO 19/20 are USB D−/D+; avoid them for normal I/O.
- GPIO 0 is a strapping pin (boot); use it as an input only with a pull-up.
- The display module usually has its own 3.3 V level shifter. Even if the module can run on 5 V: apply only 3.3 V to VCC unless a separate 3.3 V input exists.
- The backlight can be connected directly to GPIO 17. For brighter LEDs use an NPN transistor (e.g. BC547) as a switch.
- LovyanGFX is used as the display driver (not TFT_eSPI): it copes with the ESP32-S3 PSRAM and the separate touch SPI bus.
The wiring is also in the repository: WIRING.md.