Is there a way to read the vendor ID in STM32F103 series?

[SMin.1]

If you read the unique ID (96bits), you'll see 12 bytes, but you won't know if the vendor is distinguishable or not.

Also, DBGMCU_IDCODE is not known as 0xFFFF. Please let me know how to check the Vendor ID.

[Uwe Bonnes]

In the RomTable of AP0 of the debug unit, the Jedec Vendor ID can be read in the PIDR. Look in tha ARM docs for mor informations or some debugger source. Otheerwise, DBGMCU is available on F1.