There are 9 repositories under platformio-platform topic.
Espressif 32: development platform for PlatformIO
ST STM32: development platform for PlatformIO
PlatformIO development platform for IoT modules
Espressif 8266: development platform for PlatformIO
GD32V: development platform for PlatformIO
PlatformIO platform for CH32V RISC-V chips (CH32V003, CH32V103, CH32V20x, CH32V30x, CH32X035) and CH56x, CH57x, CH58x, CH59x
Atmel AVR: development platform for PlatformIO
Nordic nRF52: development platform for PlatformIO
Teensy: development platform for PlatformIO
Kendryte K210: development platform for PlatformIO
Atmel SAM: development platform for PlatformIO
Raspberry Pi: development platform for PlatformIO
Intel MCS-51 (8051): development platform for PlatformIO
ST STM8: development platform for PlatformIO
Lattice iCE40: development platform for PlatformIO
Aceinna Navigation Studio: open-source, embedded development platform for Aceinna IMU hardware. Run custom algorithms and navigation code on Aceinna IMU/INS hardware
Shakti: development platform for PlatformIO
Atmel megaAVR: development platform for PlatformIO
ASR Microelectronics ASR650x: development platform for PlatformIO
Nordic nRF51: development platform for PlatformIO
Native: development platform for PlatformIO
PlatformIO platform and framework for Artery AT32 MCU
Linux ARM: development platform for PlatformIO
TI MSP430: development platform for PlatformIO
Nuclei: development platform for PlatformIO
Scripts and examples for developing XMC Microcontroller Boards using Platform IO
SiFive: development platform for PlatformIO
Heltec Cubecell: development platform for PlatformIO
Renesas RA: development platform for PlatformIO
TI TIVA: development platform for PlatformIO
NXP LPC: development platform for PlatformIO
CHIPS Alliance: development platform for PlatformIO
Linux x86_64: development platform for PlatformIO
NXP i.MX RT: development platform for PlatformIO
GreenWaves Technologies RISC-V GAP: development platform for PlatformIO
Microchip PIC32: development platform for PlatformIO