Emulate a Sun 2/120 running NetBSD

Introduction

Getting the tme software

Making the machine-specific data

In general, any working directory filename that begins with my- or MY- is a file that is specific to your individual emulated machine. With the exception of the disk image, these are mostly text files, and you are encouraged to edit many of them to suit yourself.

% mkdir /some/where/my-sun2
% cd /some/where/my-sun2

Now populate this directory:

1. Copy the SUN2-MULTIBUS machine description file into the working directory:

   % cp /usr/pkg/share/examples/tme/SUN2-MULTIBUS ./MY-SUN2
   

   This file contains tmesh commands that create a Sun 2/120. If you don't change this file, it creates a Sun 2/120 with a bwtwo framebuffer, type-2 keyboard and mouse, one disk drive, one tape drive, and no network interface.

   If you can't use the emulated bwtwo framebuffer (because, for example, you aren't running X or didn't build tme with GTK), you must edit this file to disable the GTK-based display and enable the serial console instead. Comments in the MY-SUN2 file should explain how to do this.

2. Copy the ROM image into the working directory:

   % cp /some/where/sun2-multi-rev-R.bin .
   

3. Make a Sun 2 IDPROM file in the working directory:

   The tme-sun-idprom Perl script makes Sun IDPROM files. Before you can run it, you must choose an Ethernet address for your emulator - even if tme won't have access to the network. Ethernet addresses for Sun workstations always begin with 8:0:20, so pick three hexadecimal bytes XX:YY:ZZ such that 8:0:20:XX:YY:ZZ is not taken by any other machine on your LAN.

   % tme-sun-idprom 2/120 8:0:20:XX:YY:ZZ > my-sun2-idprom.bin
   

4. If you do want to use the GTK-based display, copy the Sun keyboards map, and keyboard macros file into the working directory:

   % cp /usr/pkg/share/examples/tme/sun-keyboards.txt .
   % cp /usr/pkg/share/examples/tme/my-sun-macros.txt ./my-sun-macros.txt
   

   You should not edit the sun-keyboards.txt file, however you may want to edit the my-sun-macros.txt file. The two files work together to transform key events on your keyboard into Sun type-2 scan codes.

   The sun-keyboards.txt file lists all of the symbols (in X terminology, all of the "keysyms") on a Sun type-2 keyboard, and gives for each keysym a Sun type-2 scan code and some modifier information. Because Sun type-2 keyboards are never going to change, you shouldn't change this file, even if you think it lists keysyms that your keyboard doesn't have, like L1, R11, etc.

   The my-sun-macros.txt file is meant to adapt your keyboard to the Sun type-2 keyboard. Any keysyms that the Sun type-2 keyboard has, that your keyboard doesn't have, can be generated by macros added to this file. For example, tmesh may complain that:

   [/display0.0]: cannot generate keysym 'R9' directly: No such file or directory
   

   The odds are good that you don't care about generating the R9 key - it's one of the keysyms on the strange, original Sun numeric keypad. But if you absolutely must be able to generate the R9 key, you could add a line similar to the following to your my-sun-macros.txt file:

   Alt_R F9 = R9
   

   Then, you could simulate pressing R9 by pressing the right Alt key and then the F9 key.

   The my-sun-macros.txt that you copied from sun-macros.txt contains a small number of macros for generating the L1, L2, etc., keys. These macros should be sufficient for general use - simply ignore the tmesh warnings about other, obscure keysyms.

   Under X, to learn about the keysyms present on your keyboard, the xmodmap -pk command will print out your current keyboard map. Alternately, the xev command may be a more convenient way to see what key combinations on your keyboard generate which keysyms.

5. Create the empty disk image file. Decide how big you want the emulated disk to be, in bytes, and substitute that number for NNNNNNNN below:

   % dd if=/dev/zero of=my-sun2-disk.img bs=1 count=1 seek=NNNNNNNN
   

   It's not immediately wasteful to choose a very large disk size - this dd command will create a disk image that initially takes up almost zero real space on your host's disk. Only as the disk is populated will your host's operating system allocate more real space to the image.

Installing NetBSD 1.6.1

Each segment of a tme virtual tape is really a regular file on your host machine. Start by creating a new directory, under your working directory, to hold the contents of this tape:

% cd /some/where/my-sun2
% mkdir my-tape
% cd my-tape

Booting the miniroot and running the install script

Notes, bugs, etc.

• The emulator doesn't keep time well at all. The emulator process itself yields whenever the NetBSD kernel inside the emulator is idle; this is good because then the emulator process doesn't consume all of the host's CPU. However, the effective clock interrupt frequency when the emulator is idling is much less than it's supposed to be. (I usually get 50Hz instead of the normal 100Hz. This might be some sort of Nyquist type effect, since the host's clock is only running at the same 100Hz?)

• tmesh has no quit command yet. The only way to terminate the emulator for now is to Control-C it.