STM32 Microcontroller Monthly Update

STM32 Latest Topics

Amazon FreeRTOS Supports STM32 Microcontrollers! Realizing a Comprehensive Solution Connecting IoT Nodes and the Cloud

STMicroelectronics announces support for Amazon FreeRTOS, provided by Amazon Web Service. This enables comprehensive solutions connecting STM32 microcontroller-based IoT nodes with the cloud, facilitating rapid development of highly connected IoT nodes.

Amazon FreeRTOS is an extension of FreeRTOS for IoT, offering libraries for secure connection between IoT nodes and the cloud, local data processing, and remote software updates, covering essential needs for IoT device development.

The Amazon FreeRTOS development board B-L475E-IOT01A is centered around the ultra-low-power STM32L475 microcontroller. It integrates Wi-Fi, Bluetooth® low energy, various sensors (motion, geomagnetic, ToF distance, temperature/humidity, MEMS microphone), providing a comprehensive development board for IoT nodes. It also features Arduino and Pmod connectors for custom functionality expansion.

Image description: An image of the STM32L4 Discovery IoT Node development board, showcasing the STM32L4 microcontroller, ARM mbed Enabled logo, and a butterfly graphic representing low power and connectivity.

Circular Display STM32L4+ Development Board Released! Ideal for Wearable Device Development.

A new development board featuring a 1.2-inch circular display for the STM32L4+ has been released. This display enables evaluation of new STM32L4+ features like Chrom-GRC™ Graphic Memory Management Unit, which reduces image buffer size by approximately 20% for circular displays. The high-resolution 16 million color, 390x390 pixel display also supports capacitive touch sensing.

The product includes MEMS microphones, an audio codec, and supports connectors for cameras, USB, headsets, and microSD cards, making it ideal for wearables and various mobile devices, offering diverse application evaluation possibilities.

Image description: An image of the circular display development board for STM32L4+.

Arm Tech Symposia 2017 Report

ST participated in the Arm Tech Symposia 2017 held at the Tokyo Conference Center Shinagawa on December 8, 2017.

At the ST booth, solutions for IoT node development and compact embedded AI engines were exhibited, attracting significant interest.

A technical session titled "More Intelligence at the Network Edge! ~Microcontroller Solutions for the Cloud Era Proposed by ST~" introduced development environments that can connect to the cloud immediately, security features required for IoT nodes, and compact embedded AI engines. By combining the high-performance and low-power STM32 with ST's extensive solutions, the presentation covered essential elements for IoT nodes, proposing concepts to reduce communication data volume and load in cloud and network environments.

Image description: An image of a presentation slide from the Arm Tech Symposia 2017 event.

STM32 Nucleo Boards and X-NUCLEO Expansion Boards: Faster, Cheaper Prototyping Methods

This month, we introduce methods for faster and cheaper prototyping without creating new PCBs. Shield boards with Arduino connectors are convenient for creating prototypes. By connecting STM32 Nucleo development boards and X-NUCLEO expansion boards via Arduino connectors, control is possible. Using Nucleo and X-NUCLEO allows starting with hardware that reliably operates without considering STM32 microcontroller or peripheral component design.

For evaluating functions not available in X-NUCLEO, custom shield boards can be created using universal boards. By incorporating circuits and Arduino connectors on these boards, custom shield boards can be completed. This allows leveraging the convenience of STM32 Nucleo and X-NUCLEO while evaluating unique functions.

Image description: An image showing an STM32 Nucleo board connected to X-NUCLEO expansion boards, illustrating the prototyping setup.

EDN Japan Series: Q&A for Learning Microcontrollers

This section introduces articles from the EDN Japan series covering microcontroller topics, including Q&A on various aspects like CISC vs. RISC, oscillator design, decoupling capacitors, latch-up, GPIO handling, LED driving, UART communication, sine/cosine wave generation, power supply connection, melody creation, EEPROM connection, ADC sampling time, microcontroller selection, DSP differences, power supply components, overrun errors, floating-point benefits, microcontroller roles, watchdog timers, Quad SPI, transistor/MOSFET selection, MCU vs. MPU, power consumption calculation, chattering, study methods, essential peripherals, interrupt handlers, low-power modes, DMA benefits, stack roles, power supply circuit design, cache memory, flash loaders, RAM instruction execution, superscalar architecture, Harvard architecture, memory types, ESD/EOS, and general I/O structure.

Image description: An image of the EDN Japan logo.

High-Resolution Timer Equipped! Arm Cortex-M4-based STM32F334

The STM32F334 is an ideal microcontroller for applications requiring very high-resolution timers, such as power and lighting control. It features an Arm Cortex-M4 core with a maximum operating frequency of 72MHz and a Floating Point Unit (FPU).

The clock, multiplied by the internal DLL, offers a minimum resolution of 217ps, enabling fine-grained PWM duty control. It also includes a 5Msps high-speed A/D converter, a 25ns response time ultra-fast comparator suitable for overcurrent/overvoltage protection, and a motor control timer with complementary outputs operating at up to 144MHz (twice the CPU clock), providing a comprehensive set of features.

Image description: A table detailing the features of the STM32F334 microcontroller, highlighting its Arm Cortex-M4 core, timers, and peripherals.

STM32 Nucleo Development Board: STM32 Microcontroller-based Open Development Platform

Image description: Logo for the STM32 Nucleo development platform.

This Month's STM32 Column: Basic STM32 Operation (43) ~Initial Value of CRC Data Register (CRC_DR)~

The initial value for CRC calculation can be defined by communication protocols or not specified. For example, it might be used by XORing the initial value 0xFFFF FFFF with the CRC calculation. The CRC_DR in the CRC calculation unit can be read from and written to, allowing users to freely set the initial value.

The default value after reset is 0xFFFF FFFF. If this default is used, it is included in the CRC calculation (refer to Application Note AN4187). If 0xFFFF FFFF is not to be included in the CRC calculation, it can be overwritten with 0x0000 0000.

Note: The SPI module also has a CRC function, but it is dedicated to SPI and does not have the feature to include initial values in the CRC calculation.

STM32 Related Document Information

Various STM32 documents can be downloaded from the following URLs. Information is categorized into Application Notes, Datasheets, Reference Manuals, User Manuals, and more, with links provided for each.

A table lists updated and newly added documents from December 2017, categorized by application note and STM32 series compatibility (F0, F1, F2, F3, F4, F7, H7, L0, L1, L4, L4+).

Image description: The ST Standard Products logo.

Data Briefs

A table lists STM32Cube MCU Packages for various STM32 series (F4, F2, L0, F0, F3, L1, F1, F7, L4/L4+, H7) and related software expansion packages like STM32 LoRa® and STM32CubeProgrammer.

Data Sheets

A table lists Data Sheets for various STM32 series (F4, L1, L4, F3) with corresponding document numbers.

Design Tips

Description of the Goertzel algorithm for computing individual terms of the discrete Fourier transform (DFT).

Errata Sheets

Lists errata sheets for STM32L496xx and STM32L4A6xx device limitations.

Programming Manuals

Lists programming manuals, including the STM32F10xxx/20xxx/21xxx/L1xxxx Cortex®-M3 programming manual.

Reference Manuals

Lists reference manuals for ultra-low-power STM32L0x3, STM32L0x2, and STM32L0x1 advanced Arm®-based 32-bit MCUs.

User Manuals

Lists user manuals for STM32 Nucleo boards, safety manuals for STM32F3 and STM32F7 series, STM32 Nucleo-144 boards, STM32 LoRa® software expansion, STM32CubeH7 demonstration platform, STM32CubeProgrammer software description, STM32 Trusted Package Creator tool, X-CUBE-SBSFU package, and STM32H7 series safety manual.

Release Notes

Lists release notes for ST-LINK server and STM32CubeProgrammer.

Ecosystem Update Information

Introduces development environments updated in December 2017, including firmware packages like X-CUBE-GNSS1, X-CUBE-LCSENSOR, X-CUBE-MEMS1, X-CUBE-MEMS-XT1, X-CUBE-SPN14, X-CUBE-USB-PD, and X-CUBE-WATSON.

Image description: The STM32 Cube logo.

Japanese Documentation Information

For Japanese versions of documents, please contact st-mcu-fun@st-jp.jp. A list of STM32 Reference Manuals (Japanese) is provided, along with links to download them.

A section lists Training Materials / Seminar Materials / STM32 Board Materials, covering various STM32 families (F0 to F7, L0 to L4, H7) and topics like STM32 Nucleo/X-Nucleo introductions, STM32Cube firmware, STemWin, STM32CubeMX with FreeRTOS, ARM Micon workshop, and specific seminar materials.

Application Notes

A comprehensive list of application notes is provided, detailing their content and compatibility with various STM32 series (F0, F1, F2, F3, F4, F7, H7, L0, L1, L4, L4+).

Leaflets

A list of leaflets describing STM32 series microcontrollers (F2, F1, F7, F0, F3, L4, F4, L0, STM32H7), development tools (STM32 Nucleo, STM32CubeMX), and ecosystems (STM32, LoRa).

EDN Japan: Q&A for Learning Microcontrollers

This section lists numerous Q&A articles from EDN Japan covering a wide range of microcontroller topics, including fundamental concepts, hardware design, software development, and best practices.

EDN Japan: Microcontroller Troubleshooting

Articles on troubleshooting microcontroller issues.

EDN Japan: How to Read Datasheets

Guides on interpreting microcontroller datasheets effectively.

EDN Japan: Microcontroller Essentials Glossary

Glossary of essential microcontroller terms.

STM32 Microcontroller Monthly Update Back Numbers

Links to previous monthly updates from April 2017 to December 2017.

Application Examples (APS Magazine Features)

A list of application examples featured in APS Magazine, highlighting STM32's performance in areas such as flight control, wearable devices, robotics, automotive, and medical applications.

STM32 Convenience: Face Recognition Solution

This month's theme is "Face Recognition Solution." ST provides various tools and solutions to reduce development load for STM32 microcontrollers. This article introduces the TeraFaces® face recognition software solution from TeraProbes.

Face detection determines if an image contains a face, while face recognition identifies whose face it is by comparing it against a database. Previously, this required high-performance processors, but TeraFaces® software, optimized for embedded devices, enables face recognition using STM32 microcontrollers without performance degradation. Its compact memory footprint (approx. 512KB ROM, 230KB RAM) allows it to fit within STM32's internal memory, significantly expanding the application scope of face recognition technology.

High-speed recognition is achieved in 0.3 seconds on STM32F4 series (max 180MHz) and 0.15 seconds on STM32F7 series (max 216MHz) for face detection to matching. The solution is offered as software IP (TeraFaces® IP for STM32) or a complete module (30x30mm, STM32F4 or STM32F7). The TeraFaces® IP for STM32 SDK is available for evaluation and application development.

Image description: A diagram illustrating the STM32 face recognition solution. It shows input from a camera, processed by a face detection library, face database creation, and face matching functions, leading to score output. The software library is indicated as the deliverable.

Companion Chip of the Month: Bluetooth® Low Energy Network Processor

BlueNRG-1Y

Bluetooth 5 compliant, with 160kbyte Flash memory, GPIO, and various peripherals. AEC-Q100 compliant.

Image description: An image of the BlueNRG-1Y Bluetooth Low Energy network processor chip, featuring ST and Bluetooth logos.

Contact Information

For product inquiries, please contact STMicroelectronics' Microcontroller Product Department or sales distributors.

STMicroelectronics (Japan) Contact:

• Microcontroller Product Department: TEL: 03-5783-8240, Email: st-mcu-fun@st-jp.jp
• Sales Department: Tokyo (03-5783-8310), Nagoya (052-259-2725), Osaka (06-6397-4130)

Sales Distributors:

• Axis Device Technology Co., Ltd.: Marketing & Sales Dept. (03-5484-7340)
• Chronix Inc.: (03-5322-7191)
• Nexxty Electronics ST Group: (03-5462-9622)
• Vitec Global Electronics Inc.: (03-3458-0301)
• Hakuto Co., Ltd. Device Solution Company: (03-3355-7635)
• Macnica Brilliant Technology Company: (045-470-9831)