Originally Posted by
trilerian
What is your opinion on the RA4M1 mcu? Granted the chip is more expensive than the 328p, but it offers up to 3x the clock speed and a lot more memory. Which would be nice since I like using the oled displays but they are memory hogs. I would like to stay with 5v vcc instead of moving to 3.3v, so I am interested in this chip. I am going to order an uno 4 for testing. Also as a huge bonus, it has a 14 bit adc instead of 10 bit. Which will be nice because another project I am working on I am adding an mcp 3204, which is a 12 bit.
I haven't had any experience with it, but looks capable. I couldn't find an Arduino core for it, but it appears to be coming since there's a new Arduino board built around it. The additional memory is nice for OLED fonts, but I've gotten better at using the tiny4k library and its built-in font scaling and can get good things happening with the 16k variants. Most of my projects are using the AVR 1-series, 2-series or Dx range. The IO on those things is really, really good and most of the features are available directly via Arduino or not hard to do with direct register setting. With the CPU clocked at 4MHz, I can get clock-rate resolution (0.25uS) on PWM signals and the 2-Series and Dx ADC can oversample to 17-bit resolution. No external crystal required too, which keeps part count down and the program uploading is much easier than ICSP. I've also used the RP2040 for native USB and it has some cool things, but the 3.3V-only thing is a bit annoying. There's a DU chip coming that will have native USB...