Edo Franzi is the designer of the famous Khepera Robot. He first developed uKOS, a multi-tasking OS for the 68k processors, as part of that project. uKOS was subsequently re-written in C and is now available, as uKOS-II, for a range of processors including the ARM Cortex M3 and M4…
When your STM32 processor starts up from a reset, there are a number of possible sources for that reset. You may want to perform different initialisations depending on the exact source of the reset. A single register holds the flags which tell you why the processor was reset. It is…
It has been more than two years since I promised myself that I would move on and build a new micromouse using the STM32 processor. Finally, I have done something about it. The new mouse is Decimus 4. (more…)
Sending data over SPI with the STM32 using polling is simple and reliable but your processor is blocked, unable to do anything else until the transfer is complete. Direct Memory Access (DMA) allows you to initiate a transfer of a block of data and then carry on doing something else…
The STM32F4xx devices are not short of pins and they can be more flexibly used than on the STM32F1xx types. On a micromouse though, there is not a lot of physical space and I am not good at routing lots of traces around a board. Since I had already decided…
In an effort to minimise the amount of space taken up on my micromouse board, I wanted to use the internal oscillator (HSI) built in to the STM32F4 device I am using. As ever, working out how to set that up in code is not obvious. However, ST do have…
The standard JTAG connector for ARM processors is the huge 20 pin IDC header. It has a whole bunch of unused pins and takes up a lot of board space. There are a several alternatives that reduce the pin count but, for a bare minimum, you can use Serial Wire Debug (SWD)… (more…)
The recently announced STM32F4 series of processors using the ARM Cortex M4 are very attractive. High speeds, large memory space and a floating point unit are among the obvious benefits although there are many other architectural changes in the ST chips. This evening, I managed to get my STM32F4-Discovery board doing something…
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STMicroelectronics, today announced the introduction of its new STM32 F4 series of microcontrollers. This extension to the STM32 platform is based on the latest ARM Cortex-M4 core, which adds signal-processing capabilities and faster operations to the already outstanding portfolio of STM32 microcontrollers; the new series, which is available now, reinforces ST’s leadership and claims the title of highest-performance Cortex-M processor-based microcontroller range in the market.
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The internal oscillator on the STM32 processors can be tuned so that an external crystal or oscillator isn’t necessary.