Emulator for Sun-2 workstation

This is a emulator for the Sun Sun-2 Workstation. It's designed to boot SunOS and emulate the display and keyboard found on an original Sun-2 worksation.

I was frustrated by the original Sun 2 emulator - tme. It's an amazing piece of software but really hard to follow internally. It seems to be an extreme example of abstraction. Perhaps too abstract, at least for me.

So I wrote this to learn about the MMU and, well SCSI. My goal is to eventually create an FPGA version of the Sun-2.

It now boots SunOS 2.0, 3.2, and 3.5 cleanly. You can install from the distribution tapes. The SCSI emulation code is still shakey for tapes, however.

SunOS 2.0 will boot multiuser and works as you'd expect.

• Converted to use SDL2
• Added an alpha quality 3C400 ethernet driver to the sun, with support for using bpf for packet input/output, it's very likely that it has lots of bugs, and it might crash

You need to configure your ethernet interface near the top of 3c400.c (under sim)
The driver sets promisicous mode, and can sniff all traffic on the interface you select to run it on, if you don't like this, don't use it!
Don't (ever!) run the emulator as root, you can chmod the BPF device files to 660 (if they aren't already) and add your user to the group set on the device to get access
Your success with communicating with the host that the emulator is running on will vary
It's best if you can use a dummy bridge interface to bind to, I used the vmnet interfaces from VMWare with a high degree of success, both in NAT and Bridged mode
If you want to route you'll need to setup proxy-arp since the Sun will ARP for any entry regardless of gateway settings, I tested parpd (https://github.com/rsmarples/parpd), and it works fine