Blue Pill Vs Black Pill: Transitioning From STM32F103 To STM32F411

For many years now, the so-called ‘Blue Pill’ STM32 MCU development board has been a staple in the hobbyist community. Finding its origins as an apparent Maple Mini clone, the diminutive board is easily to use in breadboard projects thanks to its dual rows of 0.1″ pin sockets. Best of all, it only costs a few bucks, even if you can only really buy it via sellers on AliExpress and EBay.

Starting last year, boards with a black soldermask and an STM32F4 Access (entry-level) series MCUs including the F401 and F411 began to appear. These boards with the nickname ‘Black Pill’ or ‘Black Pill 2’. F103 boards also existed with black soldermask for a while, so it’s confusing. The F4xx Black Pills are available via the same sources as the F103-based Blue Pill ones, for a similar price, but feature an MCU that’s considerably newer and more powerful. This raises the question of whether it makes sense at this point to switch to these new boards.

Our answer is yes, but it’s not entirely clearcut. The newer hardware is better for most purposes, really lacking only the F103’s dual ADCs. But hardware isn’t the only consideration; depending on one’s preferred framework, support may be lacking or incomplete. So let’s take a look at what it takes to switch. Continue reading “Blue Pill Vs Black Pill: Transitioning From STM32F103 To STM32F411”

STM32 Clones: The Good, The Bad And The Ugly

Whenever a product becomes popular, it’s only a matter of time before other companies start feeling the urge to hitch a ride on this popularity. This phenomenon is the primary reason why so many terrible toys and video games have been produced over the years. Yet it also drives the world of electronics. Hence it should come as no surprise that ST’s highly successful ARM-based series of microcontrollers (MCUs) has seen its share of imitations, clones and outright fakes.

The fakes are probably the most problematic, as those chips pretend to be genuine STM32 parts down to the markings on the IC package, while compatibility with the part they are pretending to be can differ wildly. For the imitations and clones that carry their own markings, things are a bit more fuzzy, as one could reasonably pretend that those companies just so happened to have designed MCUs that purely by coincidence happen to be fully pin- and register compatible with those highly popular competing MCU designs. That would be the sincerest form of flattery.

Let’s take a look at which fakes and imitations are around, and what it means if you end up with one. Continue reading “STM32 Clones: The Good, The Bad And The Ugly”

Macros For A Mazda

[Arik Yavilevich] recently upgraded his second-gen Mazda’s control console, going from the stock busy box to an Android head unit that does it all on a nice big touchscreen. It can also take input from the handy steering wheel buttons — these are a great option for keeping your eyes on the road and occasionally startling your unsuspecting passengers when the radio station suddenly changes.

The only problem is that [Arik]’s stock steering wheel doesn’t have any media-specific buttons on it. After a short trip to the junkyard, [Arik] had a fancier wheel to go along with the new head unit.

[Arik] doesn’t use cruise control, and those particular buttons can’t be hooked up with reprogramming the car’s computer, so he made them into macro buttons that control the head unit over Bluetooth, using an STM32 black pill board stashed in the glove box.

[Arik] found out that the cruise control buttons don’t ride the CAN bus — they use a resistor ladder/voltage divider and go directly into the ECU. After that it was mostly a matter of finding the right wires and then cutting and re-routing them to make the buttons work on the ACC setting as well as ON. A brief demo video is idling after the break.

Have an old smart phone lying around? Of course you do. Why not make your own head unit?

Continue reading “Macros For A Mazda”