Serial debug wrong output (garbage symbols)

Maverick_by_

Hello.
I just started use new ITX-3568Q mainboard with iCore-3568Q core board.
I try to use serial debug on Windows using this link:
https://wiki.t-firefly.com/en/iCore-3568JQ/debug.html#use-serial-on-windows
I use many USB to serial port adapters: CH340 and CP210 and always get garbage symbols in the Putty or MobaXterm cosole, something like this:

B~ZFZ.ZzNZj~^B2.▒▒

I tryed to set 1500000 baud rate, and 115200 and others speeds, but it didn't help.
I found information on the forum about RK3999:
Note：The default baud rate for RK3399 is 1500000,Some USB to serial chip baud rate can not support 1500000，So before you buy it, make sure it supports 1500000.

May be the reason of the problem is that my serial ports adapters does not supports 1500000 buad rate ? i see only 128000 maximum speed in the driver's port settings.
Can you gelp me with this problem ?