8237 ?

Greetings, great ALL!

I'm a little off topic, but I need to know:
How many clock cycles are actually required to transfer
one byte to/from the port(s) to/from the memory(s) of the
i8237 chip. It’s just that someone writes that 6 (!!!), someone 1, someone 2.
And how many in reality?

Sincerely, Dmitry.