Hmm, I can't get atvga to boot from disk, I just get lots of horrible beeping and error messages, even if I fool with the keyboard dip switches.
Itīs a bit tricky, because some problems with the keyboard input. Maybe a interrupt (IRQ) problem but I am not a developer.
I will tell you what I make :
Start the emulation.
Wait a while and press N
Now wait a while again, than you will see the cursor is blinking for a very short time faster (Interrupt/IRC ?)
Press than immediately the Enter-Key
If the disk is not booting, soft reset and try again.
It can be, you have to try it several times.