JogPendant_BLE

BLE HID jog pendant for ESP32 (tested on LOLIN D32), designed for CNCjs.

This project turns a physical jog wheel + selector switches into a wireless BLE keyboard pendant with dedicated function-key mapping (F13-F18) to avoid Arrow/Page key conflicts.

Photos

Pendant unit:

Wire card / color reference:

Highlights

• BLE keyboard pendant for CNC jogging
• Rotary encoder with robust detent decoding
• Axis select: X, Y, Z, Axis4
• Step modes: 1 -> no modifier, 10 -> Alt, 100 -> Ctrl
• Smooth jog modes: Shift -> smooth high, Shift + Alt -> smooth medium
• Probe trigger: Alt + P (Axis4 + 3 enable clicks)
• E-STOP lockout with LED blink and full input block

HID Mapping

Action	Key
X-	F13
X+	F14
Y+	F15
Y-	F16
Z+	F17
Z-	F18

Modifiers are applied by the selected step mode as described above.

Hardware

• ESP32 dev board (LOLIN D32 or equivalent)
• Incremental rotary encoder (A/B outputs)
• Axis selector switch (X/Y/Z/4)
• Step selector switch (1/10/100)
• E-STOP input switch
• LED + resistor (status)

Pinout

Function	GPIO	Code Symbol
Encoder A	32	ENC_A
Encoder B	22	ENC_B
Axis X	25	AXIS_X
Axis Y	27	AXIS_Y
Axis Z	14	AXIS_Z
Axis4	17	AXIS_4
Step 1	12	STEP_1
Step 10	13	STEP_10
Step 100	15	STEP_100
E-STOP	4	ESTOP
Status LED	16	LED_PIN

Wiring Notes

All inputs use INPUT_PULLUP.

• Normal state: input reads HIGH
• Active state: connect input to GND (active LOW)
• Shared GND between ESP32, switches, and encoder is required

Suggested wiring:

• Encoder A/B -> GPIO32 / GPIO22
• Selector switch commons -> GND
• Axis outputs -> GPIO25, GPIO27, GPIO14, GPIO17
• Step outputs -> GPIO12, GPIO13, GPIO15
• LED -> GPIO16 through resistor to GND

E-STOP behavior is controlled by ESTOP_PRESSED_LEVEL in code.

• Default in this project: HIGH
• If your pressed state pulls to ground, set it to LOW

Wire Color Reference (from included card)

This is based on the paper diagram shown in the photos. Wire colors can vary between production batches, so verify with continuity testing before powering the ESP32.

Signal	Color (observed)
+5V	Red
Encoder A	White
Encoder B	Black
G / common	Green
X	Yellow
Y	Yellow/Black
Z	Brown
Axis4	Brown/Black
Step 1 (X1)	Gray
Step 10 (X10)	Gray/Black
Step 100 (X100)	Orange/Black
COM	Black
E-STOP C	Blue
E-STOP CN	Blue/Black

If your card labels differ, trust the card + multimeter over this table.

CNCjs Setup

Map CNCjs jog actions to F13-F18.

Recommended mapping:

• F13 -> X-
• F14 -> X+
• F15 -> Y+
• F16 -> Y-
• F17 -> Z+
• F18 -> Z-

This keeps jog controls isolated from normal arrow/page navigation keys.

Quick Start

1. Open JogPendant_BLE/JogPendant_BLE.ino in Arduino IDE.
2. Install library: BleKeyboard (T-vK).
3. Select your ESP32 board (LOLIN D32 or equivalent).
4. Build and upload.
5. Pair the BLE device named CNC Jog Pendant.
6. Configure CNCjs hotkeys for F13-F18.

Runtime Behavior

• Jogging only works when both an axis and a step mode are selected.
• Axis4 disables jog and enables probe trigger click counting.
• If enable goes OFF, pendant sends F19 (private bridge signal).
• During E-STOP, all key output is blocked.

Troubleshooting

• No key output: confirm BLE pairing and active connection.
• No jog response in CNCjs: verify hotkeys are bound to F13-F18.
• Unstable behavior: verify only one axis and one step input are active at a time.
• Wrong E-STOP behavior: flip ESTOP_PRESSED_LEVEL between HIGH and LOW.

Credits

• BLE keyboard support is provided by T-vK/ESP32-BLE-Keyboard.

Project File

• JogPendant_BLE/JogPendant_BLE.ino