1. Introduction
The Hotspot-Face is an advanced touchscreen monitor specifically designed for DMR hotspot systems operating PI-Star. It provides real-time activity monitoring without needing a PC or mobile device.
Callsigns, talk groups, connection status, and TX duration appear instantly on a clean, dedicated display for your shack.
2. Features
Display
- 2.8" TFT touchscreen (320×240 resolution)
- Colour-coded status indicators
- Real-time DMR activity display
- Date and connection mode indicator
Network
- 2.4GHz WiFi support
- Multiple WiFi network profiles
- Auto-discovery of PI-Star devices via mDNS
- Mobile-optimized web configuration interface
Configuration
- Long-press header for options menu
- Captive setup portal (mobile/tablet)
- Network scanning and selection
- Factory reset functionality
3. Initial Setup
When powered on for the first time, the device enters WiFi Setup Mode.
Step-by-Step Instructions:
- Power the device via USB-C (5V).
-
Connect to WiFi network:
Network:Hotspot-Face Setup
Password:M3URE1512 -
Press "Sign in" if prompted
Most mobile devices will show a notification to sign in to the WiFi network. Tap this notification to open the configuration page automatically. -
Configure your settings:
- Enter your home WiFi SSID and password (or scan for networks)
- Optionally enter PI-Star IP address
- Leave PI-Star IP blank to enable automatic discovery
- Default PI-Star credentials:
pi-star/raspberry
- Click "Save & Connect" to save and reboot.
- The device will connect to your WiFi and find your PI-Star automatically.
4. Display Layout
| Section | Description |
|---|---|
| Header (Blue) | Shows device name. Long-press (3 seconds) to access options menu. |
| Status (Yellow) | Shows current status: Idle, TX (transmitting), WiFi Off, Error, etc. |
| Callsign (Purple) | Displays the callsign of the transmitting station. |
| Talk Group (Green) | Shows the active talk group or reflector. |
| Duration (Blue) | Shows the transmission duration in seconds. |
| Date (Grey) | Displays today's date (updates from NTP server). |
| Bottom Bar (Grey) | Reserved for future features. Tap to reconnect WiFi. |
5. Normal Operation
Once configured, the Hotspot-Face operates automatically:
- Automatically connects to your saved WiFi network on boot
- Uses mDNS to discover PI-Star if auto-discovery is enabled
- Fetches PI-Star activity data every 500ms for real-time updates
- Displays callsign, talk group, and TX duration when activity is detected
- Shows "TX" status in red when transmission is active
- Returns to "Idle" when no activity is present
6. Settings & Options Menu
Accessing Options Menu
Long-press the blue header bar for 3 seconds. The header will flash with a countdown, then turn green. Release to open the options menu.
Options Available:
| Option | Description |
|---|---|
| AP Setup Mode | Opens the WiFi setup portal to add more networks or change settings. |
| Factory Reset | Erases all settings and returns device to first-boot state. |
| Cancel | Returns to normal operation without changes. |
Web Configuration Settings:
| Setting | Description |
|---|---|
| Display Name | Custom text shown in the header bar (e.g., "M3URE Monitor") |
| WiFi SSID | Your home WiFi network name (supports network scanning) |
| WiFi Password | Password for your WiFi network |
| PI-Star IP | IP address of your PI-Star (optional if auto-discovery enabled) |
| PI-Star Username | Default: pi-star |
| PI-Star Password | Default: raspberry |
| Auto-Discovery | Enable mDNS automatic PI-Star detection |
7. Advanced Features
mDNS Auto-Discovery
The device can automatically find your PI-Star on the network using mDNS (Multicast DNS).
It searches for hostnames: pi-star, pistar,
pi-star.local, pistar.local
Multiple WiFi Profiles
The device stores multiple WiFi networks. You can add networks by entering AP Setup Mode and saving additional WiFi credentials without losing existing ones.
Priority Connection
The device remembers the last successfully connected network and tries that first on boot, falling back to other saved networks if connection fails.
Automatic Reconnection
If WiFi connection is lost, tap the bottom grey bar to trigger a manual reconnection attempt.
8. Factory Reset
How to Perform Factory Reset:
- Long-press the blue header bar for 3 seconds to open the options menu
- Tap the blue "Factory Reset" button
- The screen will turn red and display "RESETTING"
- Device will reboot into initial setup mode
- Reconnect using the setup instructions in Section 3
9. Troubleshooting
| Issue | Possible Cause | Solution |
|---|---|---|
| WiFi Off | Cannot connect to WiFi |
• Check WiFi password is correct • Ensure router is powered on • Move device closer to router • Check 2.4GHz WiFi is enabled (5GHz not supported) |
| No Pi-Star | Cannot find PI-Star |
• Enable auto-discovery in settings • Manually enter PI-Star IP address • Verify PI-Star is powered on and connected • Check both devices are on same network |
| Auth Error | Wrong PI-Star credentials |
• Default username: pi-star• Default password: raspberry• If changed, enter correct credentials in setup |
| Error | HTTP connection failed |
• Check PI-Star is running • Verify IP address is correct • Ensure PI-Star web interface is accessible |
| Syncing... | Time not yet synchronized |
• Wait 10-30 seconds for NTP sync • Check internet connection is active • Date will appear once NTP sync completes |
Additional Tips:
- Perform a factory reset if settings become corrupted
- Ensure USB-C power supply provides stable 5V
- Check Serial Monitor output for detailed debug information
- Tap bottom bar to force WiFi reconnection
10. Technical Information
Hardware Requirements
- Display: 2.8" touchscreen (320×240 resolution)
- Controller: microcontroller
- Power: 5V USB-C (minimum 500mA recommended)
- WiFi: 2.4GHz 802.11 b/g/n (5GHz not supported)
Software Requirements
- PI-Star: Version 3.4 or newer
Network Specifications
- Protocols: HTTP, mDNS, DNS
- AP Mode: 192.168.4.1 (captive portal)
- Update Rate: 500ms (2 updates per second)
- Discovery: mDNS hostnames (pi-star.local)
Memory & Storage
- WiFi Profiles: Stores up to 30 networks
- Retention: Settings persist across power cycles
11. Safety & Disclaimers
Operating Environment
- Indoor use only – Not weatherproof
- Dry locations only – Do not expose to moisture or liquids
- Temperature range: 0°C to 40°C operating temperature
- Ventilation: Ensure adequate airflow around device
Electrical Safety
- Use only 5V USB-C power supplies
- Do not modify internal circuitry
- Disconnect power before cleaning
- Use appropriate fusing on power supply
Disclaimers
- Device is provided "as-is" without warranty
- User assumes all risk of operation
- Not responsible for damage to PI-Star or connected equipment
- Follow your local amateur radio regulations
Responsible Use
- Comply with all amateur radio licensing requirements
- Do not use for commercial purposes without proper authorization
- Respect other users on shared talk groups
12. Support & Contact
Developer: Robert Eddy (M3URE)
Email: roberteddy1234@gmail.com
Callsign: M3URE
Manual Version: 2.1 — Updated November 2025
Getting Help
When contacting for support, please provide:
- Description of the issue
- PI-Star version
- Network configuration (WiFi vs Hotspot mode)
- Any error messages displayed