Wiring
5 wires from the control panel connector to the XIAO ESP32S3 Plus via level shifters.
Connector Pinout
Control Panel Connector (5-pin): ┌─────────────────────────┐ │ 1 2 3 4 5 │ │ ● ● ● ● ● │ └─────────────────────────┘ │ │ │ │ │ │ │ │ │ └── GND │ │ │ └─────── DATA (bidirectional, active low on press) │ │ └──────────── CLK (100kHz, active high) │ └───────────────── HOLD (chip select, active high) └────────────────────── +5V
| Pin | Name | Direction | Notes |
|---|---|---|---|
| 1 | +5V | Power | Powers the controller and level shifter |
| 2 | HOLD | Input | Chip select / frame sync, active high |
| 3 | CLK | Input | 100kHz clock, sample on rising edge |
| 4 | DATA | Bidirectional | Data in (inverted), pull low for button press |
| 5 | GND | Ground | Common ground |
Wiring Diagram
Intex 5-pin Level Shifters XIAO ESP32S3 Plus
┌──────────┐ ┌─────────────┐ ┌──────────────┐
│ +5V ●──┼────────────┼─ HV VCC ─┼─────────┼─ 5V │
│ HOLD ●──┼────────────┼─ H1 L1 ─┼─────────┼─ D5 (GPIO6) │
│ CLK ●──┼────────────┼─ H2 L2 ─┼─────────┼─ D4 (GPIO5) │
│ DATA ●──┼────────────┼─ H3 L3 ─┼─────────┼─ D3 (GPIO4) │
│ GND ●──┼────────────┼─ GND GND ─┼─────────┼─ GND │
└──────────┘ │ LV ───┼─────────┼─ 3V3 │
└─────────────┘ │ │
│ 10µF between │
│ 5V and GND │
└──────────────┘Connection Table
| From | To | Purpose |
|---|---|---|
| Intex Pin 1 (+5V) | Shifter HV + XIAO 5V | Power supply (5V) |
| Intex Pin 2 (HOLD) | Shifter H1 | Chip select (5V side) |
| Intex Pin 3 (CLK) | Shifter H2 | Clock (5V side) |
| Intex Pin 4 (DATA) | Shifter H3 | Data (5V side, bidirectional) |
| Intex Pin 5 (GND) | Shifter GND + XIAO GND | Common ground |
| Shifter L1 | XIAO D5 (GPIO6) | HOLD (3.3V side) |
| Shifter L2 | XIAO D4 (GPIO5) | CLK (3.3V side) |
| Shifter L3 | XIAO D3 (GPIO4) | DATA (3.3V side) |
| Shifter LV | XIAO 3V3 | Low voltage reference |
Important Notes
DATA is bidirectional
The BSS138 shifter handles this automatically. Don't use unidirectional shifters.
10µF capacitor
Add between 5V and GND on the ESP32 to filter power supply noise.
Level shifter required
The XIAO ESP32S3 is NOT 5V tolerant. Don't connect bus signals directly.
Keep wires short
The 100kHz clock is sensitive to capacitance. Use short, direct connections.
XIAO Pin Mapping
The XIAO ESP32S3 Plus uses D-labels on the board. We use D3, D4, D5 (GPIO 4, 5, 6) because they:
- Are general-purpose GPIO with no special boot functions
- Are adjacent on the board (D3, D4, D5) for clean wiring
- Support both input and output modes
D3 = GPIO4 | D4 = GPIO5 | D5 = GPIO6
Installation Options
Option A: Y-Splitter
Use 3D-printed connectors to create a Y-splitter. No cutting required. Original control panel stays connected.
Recommended — fully reversible
Option B: Cut & Tap
Cut the control panel cable and tap into the wires with inline splices or a junction box.
More permanent — harder to remove
Connector models: Thingiverse #4130911 by Psykokwak