Thank you for advice. I need a female to female RS232 converter to run Mconfig, will try a bit later.
Yesterday was soldering s-lead cable from midi cable and it works. Connected as daisy chain LCR speakers.

Could you help me with latest versions of firmware for DSP5200HC (coax in only), DSP7000 and 861+800v4.

https://www.Meridian-audio.com/Meridian-uploads/download/release_notes.html

I can' understand what versions are correct for me.
And what is proper way to update firmware?

HD621 , 800v4, 861v4, DSP7000, DSP5200HC