JiffyDOS and custom ROMs for C64 and C16

Hi!

I'm Commodore programmer and user also on real computers.
I have few Qs around C64 and C16
- is possible to set custom ROMs for Kernal, Basic, Chargen?
- JiffyDOS - is possible to use it, if how, and needs JiffyDOS also emulated 1541?
- C16 can have also Function ROMs - is possible to add them? Also use JiffyDOS?
- C16 core looks like supporting 1541, but is not accessible (truth is that I tried on drive - how is it?

Thank you for every help.
Miro

Hi friend!

How to contact him?
I was searching in users and found not.

In case C16 I tried to mount disk yesterday - it reported Device not present error.
Today, when you wrote that is accessible, I tried again, and is accessible, so thank you again.

Maybe you can help me with two other Qs, or recommend me anybody to contact:
1. How to save settings in case Atari 800 core - there is not accessible common menu and using F11 and F12 is there not option... so know you?
2. I need adjust Amstrad video and in menu is not any item for this, know you anything about?

Thank you for everything.
Miro

Sadly, cannot - here's message when I try to compose PM:

We are sorry, but you are not authorised to use this feature. You may have just registered here and may need to participate more to be able to use this feature.

So, where is problem?

Miro

So, here is what will be maybe useful for other users:

C16 core allows to load a custom kernal rom - how to do it is for me unknown...
C64 is written that all ROMs are inside core and no one cusom ROM is possible to add.

Miro