| 8051 | SN32F268 | ATmega32U4 | WeAct Blackpill - STM32F411 | WeAct STM32F405 | RP2040 | Proton C - STM32F303xC | Nice Nano (nRF52840) | STM32G0B1xx | |
|---|---|---|---|---|---|---|---|---|---|
| Speed | 12MHz | 48MHz | 16MHz | ~96MHz | ~168MHz | 2@ 133MHz | 72MHz | 64MHz | 64MHz |
| Voltage | 5V | 3.3V | 5V | 3.3V with 5V capable pins | 3.3V with 5V capable pins | 3.3v | 3.3V with some 5V capable pins | 3.3v | 3.3V with 5V capable pins |
| Flash size | 4kB | 32kB (~28kB usable) | 32kB (28kB usable) | 512kB | 1MB | off-chip flash, up to 16MB | 256kB | 1MB | 128-512kB |
| EEPROM size | External only | Emulated | 1kB | Emulated (with SPI SOIC footprint) | Emulated | Emulated | Emulated | Emulated | Emulated |
| Memory | 128 bytes | 2kB | 2.5kB | 128kB | 192kB | 264 kB | 48kB | 256kB | 144kB |
| Timers | 2 total | 2 total | 4 total | 11 total | 11 total | 9 total | 10 total | 8 total | 10 total |
| Digital IO | 32 pins (4 ports) | “up to 42” pins | 25 pins | 26 usable pins (more with caveats) | 45 pins (more with caveats) | 21 | 37 pins | 30 | 30+ (depending on model) |
| Architecture | 8-bit microcontroller | ARM Cortex M0 | AVR8 8-bit | ARM Cortex M4 | ARM Cortex M4 | ARM Cortex M0+ | ARM Cortex M4 | ARM Cortex M4 | ARM Cortex M0 |
| QMK Support | Out of tree | Out of tree | Fully supported | Fully supported | Fully supported | Fully supported | Fully supported | No support due to highly restricted licensing. | Fully supported |
| Cost | ~$1-3 (AliExpress) | N/A | ~$6 - Digikey | ~$6 - Digikey ~$5 -AliExpress |
~$8 - AliExpress $11 - Digikey |
$1 - Digikey $9 Adafruit KB2040 |
~$8 - Digikey | ~$6 - Digikey ~$25 NiceNano |
~$4.25 |
- Emulated eeprom uses program flash as EEPROM, reducing the total flash size.
- All controllers support external eeprom, via I2C or SPI.
- RP2040 has 2 cores, but QMK will not leverage the second one, currently.
- Prices are relative, and fluctuate