Datasheet for the STMicroelectronics STM32F205RET6, an ARM Cortex-M3 microcontroller from the STM32F2 series, in a 2.22 MB PDF. The RET6 suffix identifies the specific flash size, package and temperature range, and the document gives the pinout, power supply scheme, clock sources and electrical characteristics. Repair work typically involves locating VDD, VCAP and reset pins, checking the crystal, and finding the SWD pins for reading or reflashing firmware. Remember that read protection may prevent dumping the existing code, so plan before erasing.
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