This part is a kind of semiconductor called STM8S207RB.

Function of this product has 24 MHz STM8S 8-bit MCU.

Manufacturers : STMicroelectronics

Image and pinout :

Some of the text within the PDF file :

STM8S207xx STM8S208xx Performance line, 24 MHz STM8S 8-bit MCU, up to 128 KB Flash, integrated EEPROM, 10-bit ADC, timers, 2 UARTs, SPI, I²C, CAN Datasheet - production data Features  Core – Max fCPU: up to 24 MHz, 0 wait states @ fCPU 16 MHz – Advanced STM8 core with Harvard architecture and 3-stage pipeline – Extended instruction set – Max 20 MIPS @ 24 MHz  Memories – Program: up to 128 Kbytes Flash; data retention 20 years at 55 °C after 10 kcycles – Data: up to 2 Kbytes true data EEPROM; endurance 300 kcycles – RAM: up to 6 Kbytes  Clock, reset and supply management – 2.95 to 5.5 V operating voltage – Low power crystal resonator oscillator – External clock input – Internal, user-trimmable 16 MHz RC – Internal low power 128 kHz RC – Clock [ ... ]

STM8S207RB PDF Datasheet Download