There\u2019s plenty to choose from, but a core alone won\u2019t get us far. We need that core wrapped with memory and external interfaces. Packaging the core with these components and putting it all into a single package to create the final microcontroller is done by companies specializing in integrated circuits. These include Atmel, Cypress, Freescale, NXP, and of course ST. Since there are so many manufacturers, then\u2026<\/p>\n\n\n\n
Why ST?<\/h1>\n\n\n\n\n- Free tools for writing code, compiling it, and flashing the MCU. ST makes sure the most important things are widely available and free. As for the IDE, I recommend SW4STM32. It\u2019s the popular Eclipse modified for ST\u2019s needs.<\/li>\n\n\n\n
- Dedicated tools from ST. This includes, among others, the STM32CubeMX project skeleton generator. A great tool that speeds up the initial work with a microcontroller.<\/li>\n\n\n\n
- Free libraries for handling STM32HAL devices. They\u2019re not perfect and can be bloated, but they are great for rapid development. They let you get started quickly without diving into thousands of pages of documentation. Of course, you won\u2019t avoid it! Unfortunately, convenience often comes at the cost of performance, but it\u2019s acceptable.<\/li>\n\n\n\n
- Free STM32LL libraries. Low-layer libraries (Low Layer) for handling peripherals. Their main principle is \u2013 one function changes only one register. Here you won\u2019t manage without knowing the processor, but the optimization is top-notch.<\/li>\n\n\n\n
- Most STM32 pins are 5V tolerant<\/em>. What does this mean? You don\u2019t have to worry about level shifting when communicating with chips that operate at 5V. You need to check whether the external chip accepts the high logic level driven by the STM32. Most often this will be 3.3V. If it does (and usually it does), then goodbye level shifters.<\/li>\n\n\n\n
- Rich size and resource portfolio. You can find chips in almost any package. The most popular are TQFP 32, 48, 64, 100, 144 pins. There are even BGAs. Everyone will find something for themselves.<\/li>\n\n\n\n
- Pin compatibility within the same package in most cases (I painfully experienced one exception). If during development you run out of resources, it\u2019s not a big problem to drop in a more powerful microcontroller in the same footprint.<\/li>\n\n\n\n
- A huge number of prototyping kits. I love these kits!<\/li>\n\n\n\n
- A free programmer included with every prototyping board!<\/li>\n<\/ol>\n\n\n\n
STM32 microcontroller families<\/h2>\n\n\n\n
Across ST\u2019s MCU lineup we have several families, grouped by their capabilities. The graphic below nicely shows all models together with their performance and place in the lineup.<\/p>\n\n\n
\n![\"\"](\"http:\/\/msalamon.pl\/wp-content\/uploads\/2018\/07\/msalamon_stm32_family.jpg\")
<\/a><\/figure>\n<\/div>\n\n\n<\/p>\n\n\n\n
\n- Mainstream \u2013 general-purpose microcontrollers. The most common choice for \u201cordinary\u201d applications\n
\n- F0 \u2013 an alternative to 8- and 16-bit MCUs based on an M0 core.<\/li>\n\n\n\n
- G0 \u2013 one of the newer MCU generations with an M0+ core. Intended for low-cost applications<\/li>\n\n\n\n
- F1 \u2013 the first STM32 family based on the M3 core. High performance and an uncomplicated architecture.<\/li>\n\n\n\n
- F3 \u2013 a rich offering of analog peripherals. Intended for real-time and industrial applications.<\/li>\n\n\n\n
- G4 \u2013 another newcomer. High performance combined with a broad range of analog functions.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- High Performance \u2013 the most powerful STM32s used for computation and high data throughput. Very high core clock rates.\n
\n- F2 \u2013 a performant M3 core with a graphics accelerator. Flash up to 1 Mb; they can have, e.g., Ethernet.<\/li>\n\n\n\n
- F4 \u2013 further divided into three levels of \u201cadvancement\u201d. They have an M4 core with a floating-point unit. They can include LCD controllers with a graphics accelerator or MIPI support.<\/li>\n\n\n\n
- F7 \u2013 the latest M7 core. Peripherals similar to the M4. The most powerful single-core STM32s.<\/li>\n\n\n\n
- H7 \u2013 Dual-core STM32 (M7 as the main core + a slower M4).<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- Ultra Low Power \u2013 a series focused on the lowest possible power consumption. Lots of additional features that allow sleeping and reducing energy usage.\n
\n- L0 \u2013 the smallest in the series, starting from 14-pin.\u00a0<\/li>\n\n\n\n
- L1 \u2013 the counterpart of the F1 in a low-power version.<\/li>\n\n\n\n
- L4 \u2013 efficient and performant. They include an FPU.<\/li>\n\n\n\n
- L4+ \u2013 an extension of L4. Larger memories and graphics acceleration.<\/li>\n\n\n\n
- L5 \u2013 the newest series containing special features for security and encryption. Graphics accelerator.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- Wireless \u2013 microcontrollers with built-in wireless support, e.g., Bluetooth 5, 2.4 GHz RF. They are built with two cores \u2013 M4 and M0+<\/li>\n<\/ul>\n\n\n\n
For a more extensive description of each series, visit the manufacturer\u2019s site: https:\/\/www.st.com\/en\/microcontrollers-microprocessors\/stm32-32-bit-arm-cortex-mcus.html<\/a><\/p>\n\n\n\nWe can choose from development boards labeled as:<\/h2>\n\n\n\n\n- \n
\n- Discovery \u2013 feature-rich boards \u2013 often with high-performance MCUs \u2013 with several external components. Components used include accelerometers, gyroscopes, microphones, displays, etc. I rarely use them because I don\u2019t always need these components, and they can get in the way.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- \n
\n- Nucleo \u2013 minimalist boards somewhat reminiscent of Arduino. They generally only have the MCU together with the components required for correct operation, plus a single LED and a button. All microcontroller pins are broken out to pin headers. This is my favorite choice. Nucleo, in turn, comes in three sizes:
\n\n- Nucleo-32 \u2013 about the size of an Arduino mini and the connectors are compatible with it. Small, 32-pin MCUs. Ideal to plug permanently into a small project.<\/li>\n\n\n\n
- Nucleo-64 \u2013 probably the most popular type. 64-pin MCU. In addition to pin headers with all signals, it has an Arduino Uno\u2013compatible connector.<\/li>\n\n\n\n
- Nucleo-144 \u2013 the largest of the bunch. It carries a hefty block with as many as 144 pins, and all of that is broken out to pin headers! Next to it there\u2019s also an Arduino Uno connector. USB OTG is available, and here ST even decided to add an Ethernet connector in some versions.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
![\"\"](\"http:\/\/msalamon.pl\/wp-content\/uploads\/2020\/07\/Nucleo-64-baner.jpg\")
<\/a><\/figure>\n<\/div>\n\n\n<\/p>\n\n\n\n
Besides ST\u2019s original boards, there are many others available on the market, mostly from the Far East. Very popular is the board with an STM32F103C8T6 in an Arduino mini form factor. It costs only a dozen or so zlotys<\/strong>!<\/p>\n\n\n
STM32 microcontroller families<\/h2>\n\n\n\n
Across ST\u2019s MCU lineup we have several families, grouped by their capabilities. The graphic below nicely shows all models together with their performance and place in the lineup.<\/p>\n\n\n
<\/a><\/figure>\n<\/div>\n\n\n<\/p>\n\n\n\n
- \n
- Mainstream \u2013 general-purpose microcontrollers. The most common choice for \u201cordinary\u201d applications\n
- \n
- F0 \u2013 an alternative to 8- and 16-bit MCUs based on an M0 core.<\/li>\n\n\n\n
- G0 \u2013 one of the newer MCU generations with an M0+ core. Intended for low-cost applications<\/li>\n\n\n\n
- F1 \u2013 the first STM32 family based on the M3 core. High performance and an uncomplicated architecture.<\/li>\n\n\n\n
- F3 \u2013 a rich offering of analog peripherals. Intended for real-time and industrial applications.<\/li>\n\n\n\n
- G4 \u2013 another newcomer. High performance combined with a broad range of analog functions.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- High Performance \u2013 the most powerful STM32s used for computation and high data throughput. Very high core clock rates.\n
- \n
- F2 \u2013 a performant M3 core with a graphics accelerator. Flash up to 1 Mb; they can have, e.g., Ethernet.<\/li>\n\n\n\n
- F4 \u2013 further divided into three levels of \u201cadvancement\u201d. They have an M4 core with a floating-point unit. They can include LCD controllers with a graphics accelerator or MIPI support.<\/li>\n\n\n\n
- F7 \u2013 the latest M7 core. Peripherals similar to the M4. The most powerful single-core STM32s.<\/li>\n\n\n\n
- H7 \u2013 Dual-core STM32 (M7 as the main core + a slower M4).<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- Ultra Low Power \u2013 a series focused on the lowest possible power consumption. Lots of additional features that allow sleeping and reducing energy usage.\n
- \n
- L0 \u2013 the smallest in the series, starting from 14-pin.\u00a0<\/li>\n\n\n\n
- L1 \u2013 the counterpart of the F1 in a low-power version.<\/li>\n\n\n\n
- L4 \u2013 efficient and performant. They include an FPU.<\/li>\n\n\n\n
- L4+ \u2013 an extension of L4. Larger memories and graphics acceleration.<\/li>\n\n\n\n
- L5 \u2013 the newest series containing special features for security and encryption. Graphics accelerator.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- Wireless \u2013 microcontrollers with built-in wireless support, e.g., Bluetooth 5, 2.4 GHz RF. They are built with two cores \u2013 M4 and M0+<\/li>\n<\/ul>\n\n\n\n
For a more extensive description of each series, visit the manufacturer\u2019s site: https:\/\/www.st.com\/en\/microcontrollers-microprocessors\/stm32-32-bit-arm-cortex-mcus.html<\/a><\/p>\n\n\n\n
We can choose from development boards labeled as:<\/h2>\n\n\n\n
- \n
- \n
- \n
- Discovery \u2013 feature-rich boards \u2013 often with high-performance MCUs \u2013 with several external components. Components used include accelerometers, gyroscopes, microphones, displays, etc. I rarely use them because I don\u2019t always need these components, and they can get in the way.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- \n
- \n
- Nucleo \u2013 minimalist boards somewhat reminiscent of Arduino. They generally only have the MCU together with the components required for correct operation, plus a single LED and a button. All microcontroller pins are broken out to pin headers. This is my favorite choice. Nucleo, in turn, comes in three sizes:
\n- \n
- Nucleo-32 \u2013 about the size of an Arduino mini and the connectors are compatible with it. Small, 32-pin MCUs. Ideal to plug permanently into a small project.<\/li>\n\n\n\n
- Nucleo-64 \u2013 probably the most popular type. 64-pin MCU. In addition to pin headers with all signals, it has an Arduino Uno\u2013compatible connector.<\/li>\n\n\n\n
- Nucleo-144 \u2013 the largest of the bunch. It carries a hefty block with as many as 144 pins, and all of that is broken out to pin headers! Next to it there\u2019s also an Arduino Uno connector. USB OTG is available, and here ST even decided to add an Ethernet connector in some versions.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<\/a><\/figure>\n<\/div>\n\n\n
<\/p>\n\n\n\n
Besides ST\u2019s original boards, there are many others available on the market, mostly from the Far East. Very popular is the board with an STM32F103C8T6 in an Arduino mini form factor. It costs only a dozen or so zlotys<\/strong>!<\/p>\n\n\n
- Nucleo \u2013 minimalist boards somewhat reminiscent of Arduino. They generally only have the MCU together with the components required for correct operation, plus a single LED and a button. All microcontroller pins are broken out to pin headers. This is my favorite choice. Nucleo, in turn, comes in three sizes:
- \n