BLE Application Development with MM32W Series
💡 FAE Insights
📋 Customer Cases
Industrial Equipment Manufacturer
Industrial Automation
Challenge
Needed guidance on MCU selection and implementation
Solution
Followed LiTong FAE recommendations and best practices
Results
- Successful product launch
- Met all performance targets
Frequently Asked Questions
1. What BLE profiles are supported by MM32W?
MM32W with MindMotion BLE stack supports: (1) Standard GATT profiles - GAP (Generic Access Profile), GATT (Generic Attribute Profile), DIS (Device Information Service), BAS (Battery Service), HRS (Heart Rate Service), HTS (Health Thermometer Service), BLS (Blood Pressure Service), CGMS (Continuous Glucose Monitoring Service), and more. (2) HID over GATT - Keyboard, mouse, and custom HID devices. (3) Mesh profiles - When using BLE mesh stack (third-party or custom implementation). (4) Custom profiles - Full support for proprietary GATT-based profiles with custom services and characteristics. (5) DFU - Device Firmware Update service for over-the-air firmware updates. The BLE stack is certified and includes example implementations for common profiles. For custom applications, you can define your own services and characteristics using standard GATT mechanisms. LiTong can provide guidance on profile selection and custom profile development.
2. How do I optimize BLE power consumption?
BLE power optimization for MM32W: (1) Connection interval - Use the longest interval your application can tolerate (up to 4 seconds). This has the biggest impact on power. (2) Slave latency - Allow the slave to skip connection events (up to 499). Increases latency but reduces power. (3) TX power - Use minimum power needed for reliable communication. Reduce from +8dBm to 0dBm can halve TX current. (4) PHY selection - 1Mbps PHY is most power-efficient for small data transfers. 2Mbps is better for large transfers. (5) Advertising interval - For non-connected devices, use longer advertising intervals (1-10 seconds). (6) Data batching - Buffer multiple readings and send in one connection event rather than separate transmissions. (7) Sleep modes - Use deep sleep between BLE events. The MM32W can achieve ~15μA average in connected mode with optimized parameters. For a sensor sending 20 bytes every second, expect 20-30μA average current.
3. What is the range of MM32W BLE?
MM32W BLE range depends on PHY mode and environment: (1) 1Mbps PHY - Typical 50-100m line-of-sight, 10-30m indoors through walls. (2) 2Mbps PHY - Slightly shorter range than 1Mbps due to higher sensitivity requirements. (3) 500kbps coded PHY - Approximately 2x range of 1Mbps, 100-200m line-of-sight. (4) 125kbps coded PHY - Approximately 4x range of 1Mbps, 200-400m line-of-sight. Factors affecting range: (1) TX power - Higher power increases range but consumes more energy. (2) Antenna design - PCB antenna vs chip antenna vs external antenna. (3) Environmental obstacles - Walls, metal objects, interference. (4) Receiver sensitivity - MM32W has -97dBm sensitivity at 1Mbps. For typical indoor applications, expect 15-25m reliable range. For outdoor or large facility applications, use coded PHY for extended range. Conduct range testing in your actual deployment environment as results vary significantly.
4. How do I implement secure BLE communication?
Implementing secure BLE on MM32W: (1) Pairing - Use LE Secure Connections (Bluetooth 4.2+) with numeric comparison or passkey entry. Avoid legacy pairing (Just Works) for security-sensitive applications. (2) Encryption - All data encrypted with AES-128 after pairing. Keys stored in bonding information. (3) Authentication - Verify device identity during pairing to prevent man-in-the-middle attacks. (4) Authorization - Implement application-level authorization for sensitive operations. (5) Secure DFU - Use encrypted and signed firmware images for over-the-air updates. Verify signature before updating. (6) Key management - Store encryption keys in secure memory. Implement key rotation if long-term security required. (7) Privacy - Use resolvable private addresses to prevent device tracking. The MindMotion BLE stack implements standard Bluetooth security features. For additional security, implement application-layer encryption on top of BLE encryption. LiTong can provide guidance on security implementation and best practices.
5. What is the difference between advertising and connected modes?
BLE advertising vs connected modes: (1) Advertising mode - Device broadcasts packets periodically (20ms to 10s intervals). No connection established. Used for beacons, device discovery, and broadcasting data. Power consumption: 10-100μA average depending on interval. (2) Connected mode - Two devices establish a connection with defined interval (7.5ms to 4s). Allows bidirectional data transfer with acknowledgment. Power consumption: 15-500μA depending on interval and data rate. Use advertising mode when: Broadcasting data to multiple devices, simple beacon applications, or minimizing power when no data needs to be sent. Use connected mode when: Reliable data transfer required, bidirectional communication needed, or frequent data exchange. Some applications use both: advertise for discovery, connect when communication needed, disconnect to save power. The MM32W supports multiple advertising sets and simultaneous peripheral/central roles for flexible architectures.