Say goodbye to Bluepill, say hello to RP2040

[madias]

Warning This thread is *only* about exchanging the "Bluepill" with a similar device.

Meanwhile it is nearly impossible to get an original STM32F103RBxxx or STM32F103R8xxx, even on official distributors like Mouser they are gone.
So you get about 100% a fake or replica of the chip if you are going to buy a bluepill dev board, with guaranteed flaws like not 128kb flash memory (yeah, I know wasn't official), even worse: none or bad working USB, SPI, DMA... with random errors.
This is really bad for little projects, like my one: https://diroaudio.wordpress.com/ (sorry, german only, it's about a RFID-mp3 player for kids), because the PCBs and the code were made for the bluepill (you clamp the bluepill on the PCB).
So the question is about a new candidate:

• ESP32? Nice, but much too power hungry, even in sleep mode, too less pins.
• F401/F411 black pill? Sounds good! But: How long they will be fabricated? How long will it take until the first counterfeits are on the market? No real USB support for arduino (like mass storage)

So "ordered by accident" 5 pieces of the most hopeful candidate: The raspberry pico RP2040

• "Official" board for less than 4 EUR in local(!) stores - this is unbeatable - one(1) day delivery!
• Obsolescence Statement: RP2040 will remain in production until at least January 2030
• Dual-core Arm Cortex-M0+ processor, flexible clock running up to 133 MHz
• 264KB on-chip SRAM
• 2MB onboard Flash
• 2 × UART, 2 × SPI controllers, 2 × I2C controllers, 16 × PWM channels
• 1 × USB 1.1 controller and PHY, with host and device support
• (nearly) same form factor like the bluepill

So i tried out the Arduino repo from Earle F. Philhower, III https://github.com/earlephilhower/arduino-pico and I was really surprised in a positive way - most of all works like a charm.

So for me it's clear: The new substitute for the bluepill is the Raspberry Pico.
There are other dev boards with the RP2040, but none of them has big advantages over the "original" board, and all of them are more expensive (did I say Adafruit?)

[racemaniac]

Yeah, at the pricepoint of the picos, and the individual chips also being available at an affordable price, it can mean quite a shift.

I'm currently happy with the 401/411 blackpills, but if the same stuff happens as with the bluepills...

Let's hope they don't start making conterfeit rp2040's XD

[ag123]

RP2040 is a nice chip, I've a handful Rpi Pico shipped after several months
I tried using the pico sdk on github
https://github.com/raspberrypi/pico-sdk
they work pretty well, uses cmake and what is interesting is that the compiler used to build stm32 firmware works just well building the pico codes as well.
This saves quite a bit of space hundreds of megs.
The good thing about RP2040 is the large amount of on chip sram, the design is distinctly different in the sense that flash is off chip if I'm right about it, as like the ESP8266 and ESP32. This makes it possible to write bigger firmware such as a web server etc.

I've not really played much with my Rpi Pico other than trying the blinky and 'hello world' examples using usb-serial.
A think I kind of like about it is that the sdk is based around cmake and the api is quite well designed. Non arduino though.

I still do stm32 as by now I've quite a handful of sketches based around stm32(duino) and it is a familiar platform for me with codes that i know 'just works' for me. As i've not explored RP2040 in any depth, i'd not yet be able to make meaningful comparison between them.
But that things like stm32f4 has floating point as a 'feature' which i occasionally used in my codes, they are simply *convenient*, doing analog stuff with sensors becomes literally plug floating point equations and simply compute, the convenience of the fpu and on chip cache on f4 did make a difference with the applications. This beats using tables and interpolating values. An example, is I used it with the temperature sensor LMT86
https://www.ti.com/product/LMT86
Instead of using a large table and interpolating values, it is reduced to a single line equation fitting a quadratic model, doing square roots and all to go from voltage to temperature.
viewtopic.php?p=8834#p8834
For that purpose, one can hardly feel any delay at all, it is instantaneous.

I'd guess RP2040 has its own feature sets such as the programmable IO which I'm yet to explore.
on stm32 front I've kind of 'upgraded' to stm32f401 for things especially those that use floating point and/or use more memory e.g. drives a LCD etc
the speed difference between stm32f401 vs stm32f103 for single precision floating codes is considerably faster due to the FPU and the on-chip 'ART accelerator' cache.