Does the Intel 8051 microcontroller have a built-in crystal resonator?

Question

Microcontrollers

Hello. I started to deal with MK intel 8051 (I'm a complete novice) a question arose. I saw an oscillator in the picture of the microarchitecture. (Probably a generator).
1. Does this MK have no built-in Resonator? Those. without a resonator and having only a feedback circuit built into the MK, it is impossible to clock the MK?
2. If the answer to the first question is yes, is it possible to clock with ready-made external pulses? The internal oscillator will not change the frequency? How does it work in this case? Thanks in advance

Answer 1

1. No.
2. You can.
Why do you need this junk, if not a secret?

Answer 2

The Intel 8051 does not have a quartz resonator, that's for sure. And what, in some kind of MK there is quartz?
In fact, acquaintance with MK begins with the study of manuals, for example this one