German embedded technology firm Stackforce is using microcontrollers from ST Microelectronics for its wireless M-Bus software stack that uses the integrated sub-GHz radio and multiple modulation schemes to cut costs and increase flexibility in smart meters.
 
Developed by Stackforce, the stack complies with most of EN 13757-3/-7, covering the upper layers of the wireless M-Bus protocol stack, as well as the lower layers (EN 13757-4) and its WM-Bus modes S, T and C used throughout Europe in the 868MHz band. Mode N for operation at 169MHz is an option.
 
In addition, it meets several other metering standards, including the common Open Metering System (OMS) specification, as well as more specific standards such as Dutch Smart Meter Requirements (DSMR) or CIG Italian Gas Committee specifications.
 
Supported by the STM32 development ecosystem, STM32WL microcontrollers are low-power devices that use a range of technologies and design approaches to meet smart-meter designers’ needs.
 
“Thanks to our collaboration with Stackforce, STM32WL is reaching a new level of multi-protocol compatibility,” said Hakim Jaafar, marketing manager at Swiss firm ST Microelectronics. “With this wireless M-Bus stack, the STM32WL can become the key product for a wide range of smart-metering applications such as electricity, gas and water metering.”
 
The sub-GHz radio inside the STM32WL has a wide linear frequency range and dual power output, and can satisfy EN 300 220, FCC CFR 47 part 15, Arib T108, and other radio-equipment regulations, including China regulatory requirements, to assist development of products for markets worldwide. Other features include an integrated switched-mode power supply and hardware cryptographic accelerators.
 
“We’re proud to be chosen by STM for collaboration on the next level of embedded integration,” said David Rahusen, managing director at Stackforce. “We will shortly add a WM-Bus over LoRaWan stack that utilises unique STM32WL features to merge the benefits of WM-Bus for seamless integration into metering infrastructure with the long-range capability of LoRaWan urgently needed for metering applications.”
 
The Stackforce WM-Bus stack is available immediately. The WM-Bus over LoRaWAN stack will be available by the end of this month.
 
The STM32WL devices with up to 256kbyte flash and a BGA73 package are in production now and are supported by STM’s ten-year product-longevity commitment.