Leaflabs Maple. Arduino-style board with STM32F103RBT6 microcontroller.
The STM32 is the third ARM family by STMicroelectronics. It follows their earlier STR9 family based on the ARM9E core, and STR7 family based on the ARM7TDMI core. The following is the history of how the STM32 family has evolved.
In October 2006, STMicroelectronics (ST) announced that it licensed the ARM Cortex-M3 core.
In June 2007, ST announced the STM32 F1-series based on the ARM Cortex-M3.
In November 2007, ST announced the low-cost "STM32-PerformanceStick" development kit in partner with Hitex.
In October 2009, ST announced that new ARM chips would be built using the 90 nm process.
In April 2010, ST announced the STM32 L1-series chips.
In September 2010, ST announced the STM32VLDISCOVERY board.
In November 2010, ST announced the STM32 F2-series chips based on the ARM Cortex-M3 core, and future development of chips based on the ARM Cortex-M4 and ARM Cortex-M3 cores.
In February 2011, ST announced the STM32L-DISCOVERY board.
In March 2011, ST announced the expansion of their STM32 L1-series chips with flash densities of 256 KB and 384 KB.
In September 2011, ST announced the STM32 F4-series chips based on the ARM Cortex-M4F core and STM32F4DISCOVERY board.
In February 2012, ST announced the STM32 F0-series chips based on the ARM Cortex-M0 core.
In May 2012, ST announced the STM32F0DISCOVERY board.
In June 2012, ST announced the STM32 F3-series chips based on the ARM Cortex-M4F core.
In September 2012, ST announced full-production of STM32 F3-series chips and STM32F3DISCOVERY board. The STM32 F050-series will also be available in a TSSOP20 package.
In January 2013, ST announced full Java support for STM32 F2 and F4-series chips.
The STM32 F4-series is the first group of STM32 microcontrollers based on the ARM Cortex-M4F core. The F4-series is also the first STM32 series to have DSP and floating point instructions. The F4 is pin-to-pin compatible with the STM32 F2-series and adds higher clock speed, 64 KB CCM static RAM, full duplex I²S, improved real-time clock, and faster ADCs. The summary for this series is:
The STM32 F3-series is the second group of STM32 microcontrollers based on the ARM Cortex-M4F core, and the most recent series from ST. The F3 is almost pin-to-pin compatible with the STM32 F1-series. The summary for this series is:
The distinguishing feature for this series is presence of four fast, 12-bit, simultaneous sampling ADCs (multiplexer to over 30 channels), and interestingly, four matched, 8 MHz bandwidth OpAmps with all pins exposed and additionally internal PGA (Programmable Gain Array) network. The exposed pads allow for a range of analogue signal conditioning circuits like band-pass filters, anti-alias filters, charge amplifiers, integrators/differentiators, 'instrumentation' high-gain differential inputs, and other. This eliminates need for external OpAmps for many applications. The built-in two-channel DAC has arbitrary waveform as well as a hardware-generated waveform (sine, triangle, noise etc.) capability. All analogue devices can be completely independent, or partially internally connected, meaning that one can have nearly everything that is needed for an advanced measurement and sensor interfacing system in a single chip.
The four ADCs can be simultaneously sampled making a wide range of precision analogue control equipment possible. It is also possible to use a hardware scheduler for the multiplexer array, allowing good timing accuracy when sampling more than 4 channels, independent of the main processor thread. The sampling and multiplexing trigger can be controlled from a variety of sources including timers and built-in comparators, allowing for irregular sampling intervals where needed.
The op-amps inputs feature 2-to-1 analogue multiplexer, allowing for a total of eight analogue channels to be pre-processed using the op-amp; all the op-amp outputs can be internally connected to ADCs.
The STM32 F2-series of STM32 microcontrollers based on the ARM Cortex-M3 core. It is the most recent and fastest Cortex-M3 series. The F2 is pin-to-pin compatible with the STM32 F4-series. The summary for this series is:
Static RAM consists of 64 / 96 / 128 KB general purpose, 4 KB battery-backed, 80 bytes battery-backed with tamper-detection erase.
Flash consists of 128 / 256 / 512 / 768 / 1024 KB general purpose, 30 KB system boot, 512 bytes one-time programmable (OTP), 16 option bytes.
Each chip has a factory-programmed 96-bit unique device identifier number.
Common peripherals included in all IC packages are USB 2.0 OTG HS, two CAN 2.0B, one SPI + two SPI or I²S), three I²C, four USART, two UART, SDIO/MMC, twelve 16-bit timers, two 32-bit timers, two watchdog timers, temperature sensor, 16 or 24 channels into three ADCs, two DACs, 51 to 140 GPIOs, sixteen DMA, real-time clock (RTC), cyclic redundancy check (CRC) engine, random number generator (RNG) engine. Larger IC packages add 8/16-bit external memory bus capabilities.
The STM32 F1-series was the first group of STM32 microcontrollers based on the ARM Cortex-M3 core and considered their mainstream ARM microcontrollers. The F1-series has evolved over time by increasing CPU speed, size of internal memory, variety of peripherals. There are five F1 lines: Connectivity (STM32F105/107), Performance (STM32F103), USB Access (STM32F102), Access (STM32F101), Value (STM32F100). The summary for this series is:
TM32L432KC in UFQFPN32 package, ARM 32-bit Cortex-M4 core, 80 MHz max CPU frequency, VDD from 1.65 V to 3.6 V, 256 KB Flash, 64 KB SRAM, Timers General Purpose (4), SPI/I2S (2), I2C (2), USART (2), 12-bit ADC with 10 channels (1), GPIO (20) with external interrupt capability, RTC, Random Generator (TRNG for HW entropy).
Static RAM consists of 10 / 16 / 32 / 48 / 80 KB general purpose, 80 bytes with tamper-detection erase.
Flash consists of 32 / 64 / 128 / 256 / 384 / 512 KB general purpose with ECC, 4 / 8 KB system boot, 32 option bytes, EEPROM consists of 4 / 8 / 12 / 16 KB data storage with ECC.
Each chip has a factory-programmed 96-bit unique device identifier number.
Common peripherals included in all IC packages are USB 2.0 FS, two SPI, two I²C, three USART, eight 16-bit timers, two watchdog timers, temperature sensor, 16 to 24 channels into one ADC, two DACs, 37 to 83 GPIOs, seven DMA, real-time clock (RTC), cyclic redundancy check (CRC) engine. The STM32FL152 line adds a LCD controller.
Oscillators consists of internal (16 MHz, 38 kHz, variable 64 kHz to 4 MHz), optional external (1 to 26 MHz, 32.768 to 1000 kHz).
STMicroelectronics provides a selection of STM32 microcontrollers ready to be used with Java programming language. This special series embeds the required features to execute Java programs. They are based on the existing STM32 F1, F2, F4, F0, L0 families. There are two sets of special part numbers enabled for Java: Production part numbers end in the letter "J", and sample part numbers end in the letter "U".
All Nucleo boards by STMicroelectronics support the mbed IDE development, and has an additional onboard ST-LINK/V2-1 host adapter chip that supplies SWD debugging, virtual COM port, mass storage. There are three Nucleo board families, each supporting a different microcontroller IC package footprint.
This family has 144-pin STM32 ICs, Arduino Uno Rev3 female headers, ST Zio female headers, ST morpho male pin headers (two 19x2), second Micro-AB USB connector, and RJ45Ethernet connector (some boards).
Low power ICs are n/a. Mainstream IC is F303. High performance ICs are F207, F412, F429, F446, F746, F767.
STM32VLDISCOVERY board with STM32F100RBT6 microcontroller.
The following Discovery evaluation boards are sold by STMicroelectronics to provide a quick and easy way for engineers to evaluate their microcontroller chips. These kits are available from various distributors for less than US$20. The STMicroelectronics evaluation product licence agreement forbids their use in any production system or any product that is offered for sale.
Each board includes an on-board ST-LINK for programming and debugging via a Mini-B USB connector. The power for each board is provided by a choice of the 5 V via the USB cable, or an external 5 V power supply. They can be used as output power supplies of 3 V or 5 V (current must be less than 100 mA). All Discovery boards also include a voltage regulator, reset button, user button, multiple LEDs, SWD header on top of each board, and rows of header pins on the bottom.
An open-source project was created to allow Linux to communicate with the ST-LINK debugger.
This board includes an integrated ST-LINK/V2 debugger via Mini-B USB connector, accelerometer/compass (LSM303DLHC), gyroscope (L3GD20), 8 user LEDs, user button, reset button, Full-Speed USB to second Mini-B USB connector, and two 25x2 male pin headers.
This board includes an integrated ST-LINK/V2 debugger via Mini-B USB connector, gyroscope (L3GD20), 4 user LEDs, user button, reset button, linear touch keys, Full-Speed USB to second Mini-B USB connector, and two 33x1 male pin headers.
It contains two boards, each with a STM32W108 SoC microcontroller in VFQFPN40 and VFQFPN48 packages.
The evaluation board has a built-in 2.4 GHz IEEE 802.15.4 transceiver and Lower MAC (so supports 802.15.4, ZigBee RF4CE, ZigBee Pro, 6LoWPAN (Contiki) wireless protocols). The SoC contains 128-Kbyte flash and 8-Kbyte RAM memory. Flash memory is upgradable too via USB. It has an ARM Serial Wire Debug (SWD) interface (Remote board) and is designed to be powered by USB or with 2 AAA batteries (Remote board). There are two user-defined LEDs (green and yellow) and five push buttons to create easy-to-use remote functions (Remote board).
A ready-to-use Java development kits for its STM32 microcontrollers. The STM3220G-JAVA Starter Kit combines an evaluation version of IS2T's MicroEJ® Software Development Kit (SDK) and the STM32F2 series microcontroller evaluation board providing everything engineers need to start their projects. MicroEJ provides extended features to create, simulate, test and deploy Java applications in embedded systems. Support for Graphical User Interface (GUI) development includes a widget library, design tools including storyboarding, and tools for customizing fonts. STM32 microcontrollers that embed Java have a Part Number that ends with J like STM32F205VGT6J.
It contains a STM32F103RBT6 microcontroller at 72 MHz with 128 KB flash and 20 KB RAM in LQFP64 package.
This board also includes in-circuit debugger via USB, 3 V battery, LEDs, edge card connector.
The price is approximately US$65.
EvoPrimers for STM32
A prototyping environment for a variety of STM32 variants, which allows users to create their applications using an application programming interface (API) to implement device peripherals and a range of evaluation features on the EvoPrimer base including TFT color touchscreen, graphical user interface, joy stick, codec-based audio, SD card, IrDA and standard peripherals such as USB, USART, SPI, I2C, CAN, etc.
EvoPrimer target boards are available for several variants including STM32F103, STM32F107, STM32L152 and STM32F407.
The EvoPrimer base includes a device programming and application debugging interface and comes with a Raisonance software tool set for coding, compiling and debugging the user's application.
The CircleOS utility allows the user to code their applications relying on an application programming interface, making it possible to program the application without having to master the configuration of device peripherals.
STM32CubeMX, by STMicroelectronics, a freeware package for Windows, Mac OS X and Linux that is a graphical software configuration tool that allows generating C initialization code using graphical wizards. The package was first release in February 2014 with graphical peripheral allocation support for every STM32 chip. As of January 2015, the tool supports all STM32 series. It can generate source code usable directly on the most current ARM Cortex-M IDEs, including the free System Workbench for STM32 IDE. The source code generated by STM32CubeMX is licensed under the 3-clause BSD License, making it suitable for commercial as well as open source applications. STM32CubeMX is likely an evolution of the former MicroXplorer tool, because the saved "IOC" configuration file from STM32CubeMX shows the word "MicroXplorer" in it. A 32-bit Java Runtime Environment (JRE) must be installed prior to running STM32CubeMX.
STM-STUDIO, by STMicroelectronics, a freeware package for Windows to help debug and diagnose STM32 applications while they are running by reading and displaying their variables in real-time. STM-STUDIO connects to any STM32 using any ST-LINK type of device via JTAG or SWD debug bus protocols. It can log captured data to a file and replay later. It parses debugging information from the ELF application executable file. A 32-bit Java Runtime Environment (JRE) must be installed prior to running STM-STUDIO. The STM32 ST-LINK Utility must be installed prior to running STM-STUDIO.
System Workbench for STM32, by Ac6, a freeware IDE running on Windows, Linux and Mac OS X to develop, debug and diagnose STM32 applications. System Workbench for STM32 can be used to develop on any STM32 using any ST-LINK/V2 type of device via JTAG or SWD debug bus protocols. It is based on Eclipse and the GNU GCC toolchain and supports out-of-the-box all ST-provided evaluation boards (Eval, Discovery or Nucleo). A 32-bit Java Runtime Environment (JRE) will automatically be installed if needed as well as the STM32 ST-LINK driver.
STM32 ST-LINK Utility, by STMicroelectronics, a freeware package for Windows to perform in-system programming of STM32 microcontrollers using the USB-based ST-LINK/V2 interface device via JTAG or SWD debug bus protocols. This software can upgrade the firmware in the ST-LINK device, which includes the embedded ST-LINK on all of the STM32 DISCOVERY boards. During installation of this utility, a USB driver is installed to provide a communication interface with the ST-LINK device, which in turn also allows various IDEs to use the ST-LINK for debugging.
ST Visual Programmer (STVP), by STMicroelectronics, a freeware package for Windows to perform in-system programming of the flash in STM32 microcontrollers using a USB-based ST-LINK device.
DfuSe, by STMicroelectronics, a freeware package for Windows to load DFU programs into the flash of USB-based STM32 microcontrollers.
pystlink, an opensource ST-LINK/V2 programmer and debug tool with simple command-line interface for Linux, Mac OS X and Windows written in Python 3.
Flash programming via USART
All STM32 microcontrollers have a ROM'ed bootloader that supports loading a binary image into its flash memory using one or more peripherals (varies by STM32 family). Since all STM32 bootloaders support loading from the USART peripheral and most boards connect the USART to RS-232 or a USB-to-UART adapter IC, thus it's a universal method to program the STM32 microcontroller. This method requires the target to have a way to enable/disable booting from the ROM'ed bootloader (i.e. jumper / switch / button).
The amount of documentation for all ARM chips is daunting, especially for newcomers. The documentation for microcontrollers from past decades would easily be inclusive in a single document, but as chips have evolved so has the documentation grown. The total documentation is especially hard to grasp for all ARM chips since it consists of documents from the IC manufacturer (STMicroelectronics) and documents from CPU core vendor (ARM Holdings).
A typical top-down documentation tree is: manufacturer website, manufacturer marketing slides, manufacturer datasheet for the exact physical chip, manufacturer detailed reference manual that describes common peripherals and aspects of a physical chip family, ARM core generic user guide, ARM core technical reference manual, ARM architecture reference manual that describes the instruction set(s).
STM32 documentation tree (top to bottom)
STM32 marketing slides.
STM32 reference manual.
ARM core website.
ARM core generic user guide.
ARM core technical reference manual.
ARM architecture reference manual.
STMicroelectronics has additional documents, such as: evaluation board user manuals, application notes, getting started guides, software library documents, errata, and more. See External Links section for links to official STM32 and ARM documents.