China, June 9, 2021 – STMicroelectronics announces that the development verification of the new X-CUBE-IOTA1 extension package has been completed and is now available for download to accompany the IOTA Foundation’s distributed ledger technology (DLT) and infrastructure upgrade to Chrysalis version. New expansion packages, including the integrated IOTA C software library, have been added to the STM32Cube microcontroller software development ecosystem.

STMicroelectronics updates STM32Cube software package to support IOTA Chrysalis version

STM32Cube integrates low-level software and middleware into a software library, and also integrates a microcontroller configuration tool that generates initialization code, allowing embedded applications to run on any microcontroller in the popular STM32 series. With over 100 expansion packs, including the updated X-CUBE-IOTA1, the STM32Cube software is an ever-expanding ecosystem of development resources to which other use-case-specific software can be added.

The new extension includes IOTA-specific middleware and sample code, and developers can use the latest upgrade of IOTA DLT’s Chrysalis system to develop smart and connected transaction processing devices through energy-efficient and highly functionally integrated STM32 MCUs.

IOTA DLT technology, also known as Tangle, is a distributed security database that prevents data tampering. According to the IOTA Foundation, Chrysalis’ new upgraded protocol is 60% more energy efficient than IOTA’s original protocol. To realize these benefits, the IOTA Foundation upgraded the protocol to atomic transactions, which record state changes more efficiently than an “account transaction model” that requires updating the entire account balance. Atomic transactions reduce the minimum transaction data size from the original 3500 bytes to 275 bytes. The improved new transaction selection algorithm also enables faster transaction verification and synchronization. According to the IOTA Foundation, 1 Bitcoin transaction uses electricity to allow the IOTO system to perform 600 million transactions.

The latest version of the X-CUBE-IOTA1 software supports the IoT node evaluation board B-L4S5I-IOT01A development kit, which is equipped with an STM32L4+ microcontroller and connects to the Internet via a Wi-Fi interface. The new upgrade package relies on STM32 Cryptolib to provide highly optimized and robust security algorithms, including:

1 Middleware library:

1 IOTA Client API for applications to interact with the Tangle database

2 STM32 encryption library for encryption, hash conversion, message authentication and digital signature

3 Transport Layer Security (MbedTLS)

4 FreeRTOS

5 Wi-Fi management

● Full drivers for access to onboard motion and environmental sensors

The X-CUBE-IOTA1 expansion package is now available for download from

The Links:   LQ156M1LG21 G170ETN020