STM32F407 STM32 System ARM Core Development Board Cortex-M4 Single-Chip Starter | eBay
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M4 core ARM/STM32 Microcontroller Single-Chip Learning Board STM32F405RGT6 STM32 System Board Development Board For LCD Screen - AliExpress
SMD STM32F103C8T6 STM32F103 STM32 LQFP48 MCU ARM ST IC at Rs 300/piece in Thane