SDAA486 September   2026 CC1312R

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Smart Meter EU Regulations
    2. 1.2 Rotary Metrology Designs
  5. 2Smart Flow Meters and Sub-Metering Devices
    1. 2.1 Heat Cost Allocator (Sub-Metering)
      1. 2.1.1 HCA Key Functions
        1. 2.1.1.1 IrDA Communication Port
        2. 2.1.1.2 Temperature Measurement (Two-Sensor Method)
        3. 2.1.1.3 Segment LCD Support
    2. 2.2 Retrofit Add-On Module for Mechanical Water Meters
      1. 2.2.1 Retrofit Add-On Module Key Functions
      2. 2.2.2 Rotary Flow Metrology Implementation
        1. 2.2.2.1 Optical and Magnetic Rotary Sensing
        2. 2.2.2.2 Inductive Rotary Sensing
      3. 2.2.3 IrDA Wake-Up Detection
    3. 2.3 Smart Rotary Water Meter
      1. 2.3.1 Water Meter Key Functions
      2. 2.3.2 Segment LCD with CapTouch Activation
      3. 2.3.3 Tamper Detection With TMAG5231
      4. 2.3.4 OMS Compliant wM-Bus Communication Sub-system
    4. 2.4 Thermal Meters (Heat / Cold)
      1. 2.4.1 Thermal Meter Key Functions
      2. 2.4.2 Analog Signal Chain for DTM
      3. 2.4.3 Remarkable, Fully Digital Design for DTM
        1. 2.4.3.1 I2C and SMBus-Compatible Digital Sensor for Thermal Meters
        2. 2.4.3.2 1-Wire Compatible Digital Sensor for Thermal Meters
    5. 2.5 Bluetooth Low Energy (BLE) in Flow Meters
    6. 2.6 Influence of CRA on Smart Flow Meters and Heat Cost Allocators
      1. 2.6.1 Achieving CRA Conformance Through Careful System Design
        1. 2.6.1.1 Tamper Detection as a Physical Security Argument
        2. 2.6.1.2 Secure Key Storage
        3. 2.6.1.3 Secure Boot
        4. 2.6.1.4 Authenticated wM-Bus Communication
        5. 2.6.1.5 Secure Firmware Update via Over-the-Air Download (OAD)
        6. 2.6.1.6 Security Event Logging
  6. 3Summary
  7. 4References

1.2 Rotary Metrology Designs

The metrology function is the key feature, provided by any smart meter device; there are multiple electronic sensing technologies that have been used for decades, with each having advantages and disadvantages.

TI has released the MSP430FR6989 EVM in combination with additional HW, supporting the three most popular sensing methods for the rotary flow meters sensing: inductive (LC-sensing), optical, and magnetic. These reference designs address the high-volume flow metering end equipment, such as hot-water and cold-water meters (popular in Germany), the Retrofit Add-On modules for mechanical meters as well as sub-metering applications, which include both Heat meters and Heat Cost Allocators.

Note that besides rotary flow meters, which still are the dominant technology world-wide, there is also the UltraSonic flow measurement, supported by TI's MSP430FR6043 device family, with ultrasonic flow metering gaining traction in many markets world-wide.

This document focuses on rotary sensing designs with CC1312R, CC1312R7, and CC1314R10 Wireless MCUs, which in many cases allow the development of higher integrated, CRA-compliant designs at the cost of slightly increased power consumption versus MSP430FR6989.

The results presented in this document utilize extensively the ultra-low power SCE module inside the CC1312 and CC1314 device families and prove that integrating rotary metrology, IrDA communications, segment LCD display control with GPIOs, and magnetic tampering in the SCE is feasible.

The market leading ultra-low power consumption numbers, documented in the following sections, are the foundation for developing single-chip metering and sub-metering devices at lower total system cost due to the integrated Sub-1GHz radio and SCE module.