How to create a Raspberry QEMU VM emulating the physical hardware as close as possible

[jmqemuml]

Hello everyone, 

I have a Raspberry Pi 4 model B v1.4 with 8GB RAM, and I need to create a VM in 
it as close to the physical hardware as possible (no need to be the exact RPi4 
hardware, RPi3 or RPi2 would also work).

The reason is because I need to run this semi-closed software which comes only 
in a bootable SD image: 
https://github.com/victronenergy/venus/wiki/raspberrypi-install-venus-image

The host RPi is running Devuan Chimaera 4.0 (systemd-less Debian Bullseye 
derivative) and I'm using the QEMU v6.1 packages straight from its backports 
repo.

I've got so far as to extracting the image and trying to run it with 

        qemu-system-arm -M raspi2b -vnc :50 -drive 
file=~/tape/victron/venusos_rpi/venus-image-raspberrypi2-20210411203709-v2.66.rootfs.rpi-sdimg,format=raw,index=0,media=disk

The result is that the QEMU process starts and keeps running, and I can connect 
via VNC to port 5950 to see the VM screen, but VNC shows only a black screen. 

What am I doing wrong? Has anyone managed to emulate a physical RPi in QEMU yet?

Additionally, hints on how to debug this or other things to try would be most 
welcome.

Cheers, 
--
  Durval Menezes.