How to Set up TTYLinux under BOCHS

How to Set Up ttylinux
under the Bochs Emulator

Web Presentation and Text Copyright©2013 by Daniel B. Sedory;
except for any direct quotes or images from Bochs or ttylinux, of course.
(NOT to be reproduced in any form without Permission of the Author !)

If you have not yet done so, please install the Bochs Emulator under your OS Platform. Although most of the following will apply only to those using Microsoft® Windows™, some of this page will also be useful to those running a Linux distribution as well. To install Bochs, please see our How to Set Up and Run the Bochs Emulator page with dlxlinux, and be sure to download the ttylinux-virtio_i486-16.1.iso.gz file from the ttylinux web site.

The following assumes you already have BOCHS installed on your PC, and know how to navigate to its install location. On a Windows™ PC, this should be: "C:\Program Files\Bochs-2.6.2\" (or whatever current version of Bochs is installed as the folder name). Let's begin:

NOTE: If you simply want to learn about various linux commands using the ttylinux .ISO file, there's no need to create a new disk image under Bochs or to use another directory. Simply edit the "bochsrc.bxrc" file in the dlxlinux folder according to steps 9 - 11 below, and you can boot-up from the Virtio i486 (or try some other CD image file; note: others may require a lot more memory and take much longer to boot-up!) as shown in steps 14 - 16. Compared to dlxlinux, these image files have most, if not all, of the essential commands, and none are 'broken'; e.g., "shutdown -h" will actually shut off the emulation and there's a "halt" function as well, which will stop the OS, but not poweroff the emulation. And they all run on much more recent Linux kernel versions.

1. Create a new subfolder under your main Bochs install folder and label it: ttylinux.
2. Extract the ttylinux-virtio_i486-16.1.iso from the *.gz file into the ttylinux folder using 7-Zip, WinRAR or anything else that allows you to do so.
3. Copy the file "bochsrc.bxrc" from the dlxlinux folder under your Bochs install folder into the ttylinux folder.

4. Copy the file "bximage.exe" from the main Bochs folder into the ttylinux folder.
5. Execute (double-click on) bximage.exe in the ttylinux folder.
6. Answer the questions it asks as follows ( YELLOW is what action to take, and GREEN shows what we entered):

========================================================================
                                bximage
                  Disk Image Creation Tool for Bochs
          $Id: bximage.c 11315 2012-08-05 18:13:38Z vruppert $
========================================================================

Do you want to create a floppy disk image or a hard disk image?
Please type hd or fd. [hd]  Press ENTER key!

What kind of image should I create?
Please type flat, sparse or growing. [flat]  Press ENTER key!

Enter the hard disk size in megabytes, between 1 and 8257535
[10] 180  Type 180, then press ENTER key!

I will create a 'flat' hard disk image with
  cyl=365
  heads=16
  sectors per track=63
  total sectors=367920
  total size=179.65 megabytes

What should I name the image?
[c.img] hda.img  Type hda.img, then press ENTER key!

Writing: [] Done.

I wrote 188375040 bytes to hda.img.

The following line should appear in your bochsrc:
  ata0-master: type=disk, path="hda.img", mode=flat, cylinders=365,
 heads=16, spt=63
(The line is stored in your windows clipboard, use CTRL-V to paste)

Press any key to continue
_

Note: Even though this image file is supposed to be created 'flat' its name and information often appear in a BLUE font under a Windows OS, which indicates a 'sparse' (or compressed) file; that is, not all 180 MiB is written to disk, but rather a much smaller file which simply notes which small number of bytes (from 1 or more) it contains and where, since the much larger remaining portion is composed of only zero bytes! Do this: 'Right-click' on the file name, open 'Properties' and click on the "Advanced..." button. If you see a checkmark in the checkbox next to "Compress contents to save disk space" then un-checking it and clicking on 'OK' and the "Apply" button will cause all 188,375,040 bytes to be written out to disk.

[Some math (You can skip this if not interested!): This image file is comprised of 367,920 sectors (of 512 bytes each), and when using a disk geometry of 16 Heads (0 - 15) and 63 Sectors, this works out to exactly 365 full cylinders (0 - 365); no 'surplus' sectors, where the last sector on the disk is CHS: (364, 15, 63) or LBA 367,919 (0 - 367919). 512 bytes/sector x 63 sectors/head x 16 head/cylinder x 365 cylinders = 188,375,040 bytes.]

7. Open the file "bochsrc.bxrc" in a text editor (Windows users should be able to 'right-click' on the file name and choose 'Edit' from the menu; opening the file in Notepad). Replace the "ata0-master..." line containing the dlxlinux "hd10meg.img" file with:

ata0-master: type=disk, path="hda.img", mode=flat, cylinders=365, heads=16, spt=63

And leave the file open.

8. Close the bximage.exe window after you've entered the stored line (just in case it didn't store correctly).
9. Add the following line under the one you replaced above:

ata0-slave: type=cdrom, path="ttylinux-virtio_i486-16.1.iso", status=inserted

10. Locate the "boot: c" line. Comment-out that line and add one for a CD-ROM drive as shown here:

#boot: c
boot: cdrom

11. We'd also recommend changing the first line (for the amount of available Memory) from "megs: 32" to "megs: 128".
12. Creating two blank floppy diskettes to use for saving data to and from the ttylinux disk drive image would also be recommended, before deleting bximage.exe from the folder:

========================================================================
                                bximage
                  Disk Image Creation Tool for Bochs
          $Id: bximage.c 11315 2012-08-05 18:13:38Z vruppert $
========================================================================

Do you want to create a floppy disk image or a hard disk image?
Please type hd or fd. [hd] fd  Type fd, then press ENTER key!

Choose the size of floppy disk image to create, in megabytes.
Please type 0.16, 0.18, 0.32, 0.36, 0.72, 1.2, 1.44, 1.68, 1.72, or 2.88.
 [1.44]  Press ENTER key!
I will create a floppy image with
  cyl=80
  heads=2
  sectors per track=18
  total sectors=2880
  total bytes=1474560

What should I name the image?
[a.img]  Press ENTER key! (Change to b.img 2nd time through.)

Writing: [] Done.

I wrote 1474560 bytes to a.img.

The following line should appear in your bochsrc:
  floppya: image="a.img", status=inserted
(The line is stored in your windows clipboard, use CTRL-V to paste)

Press any key to continue
_

13. If you installed BOCHS under Windows and see the special 'bochs (box) icon' next to your *.bxrc file, then you should be able to simply 'right-click' on the bochsrc.bxrc file and choose Run from the menu in order to start the Bochs Emulator; otherwise copy the "run.bat" file from the "dlxlinux" folder into this one, and edit it appropriately, such as:

cd "C:\Program Files\Bochs-2.6.2\ttylinux"
..\bochs -q -f bochsrc.bxrc

14. After the Bochs Emulator starts booting-up from the ttylinux CD, you should briefly see this screen:

15. Eventually, after displaying many lines about its progress and pausing for a while at some lines (such as "RAMDISK: gzip image found at block 0"), you should see the following (also REMEMBER that it is very common for the Bochs window to turn completely BLACK; that is, 'blank out'. Simply press a 'SHIFT' key if this happens!):

16. Enter root as the 'login name' and password as the 'password' and the CD will respond with: "Chop wood, carry water." and a Unix/Linux prompt (#).

17. Entering "fdisk -l" (the l switch lists all partitions on a disk) at this command prompt will show there are currently no partitions on the disk:

# fdisk -l

Disk /dev/hda: 188 MB, 188375040 bytes
255 heads, 63 sectors/track, 22 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/hda doesn't contain a valid partition table

Note: Even though Bochs created the disk image file using 365 cylinders having only 16 heads, this 'BusyBox' version of fdisk defaulted to using cylinders having 255 heads each (it also enforces cylinder boundaries, meaning a partition could only be created as a multiple of 512 bytes/sector x 63 sectors/head x 255 heads = 8,225,280 bytes), so attempting to set a partition to a capacity of 24 MiB (25,165,824 bytes) would result in one actually having 4 cylinders = 32,901,120 bytes (or about 31 MiB) because 3 cylinders would be too small (about 23.5 MiB). We can, however, adjust how fdisk functions, to create partitions using a geometry of only 16 heads per cylinder (see instructions below).

So we must create some partitions on the empty disk image first (later, the ttylinux install script will format the partitions according to how we set up its configuration file). At the command prompt, enter "fdisk /dev/hda". And ttylinux will respond with (you ENTER what's shown in the GREEN font and note or do what's shown in the YELLOW font):

# fdisk /dev/hda
Device contains neither a valid DOS partition table, nor Sun, SGI, OSF or GPT di
sklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that the previous content
won't be recoverable.


Command (m for help): c  (ENTER c to turn off DOS Compatibility.)
DOS Compatibility flag is not set

Command (m for help): x  (ENTER x to access additional 'expert' commands.)

Expert command (m for help): c  (ENTER c to change number of cylinders.)
Number of cylinders (1-1048576, default 22): 365  (ENTER 365.)

Expert command (m for help): h  (ENTER h to change number of heads.)
Number of heads (1-256, default 255): 16  (ENTER 16.)

Expert command (m for help):r  (ENTER r to return to main menu.)

Command (m for help): n  (ENTER n to create a new partition.)
Command action
   e   extended
   p   primary partition (1-4)
p  (ENTER 'p' to create a primary partition.)
Partition number (1-4): 1  (ENTER a 1.)
First cylinder (1-365, default 1):  Press the ENTER key (to use '1')!
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-365, default 365): 49
                                                                 (ENTER 49.)
Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 2  (ENTER a 2.)
First cylinder (50-365, default 50):  Press the ENTER key (to use '50')!
Using default value 50
Last cylinder or +size or +sizeM or +sizeK (50-365, default 365): 114
                                                                  (ENTER 114.)
Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 3  (ENTER a 3.)
First cylinder (115-365, default 115):  Press the ENTER key (to use '115')!
Using default value 115
Last cylinder or +size or +sizeM or +sizeK (115-365, default 365): Press the
Using default value 365                                          ENTER key!

Command (m for help): p  (ENTER 'p' to print summary of partition table.)

Disk /dev/hda: 188 MB, 188375040 bytes
16 heads, 63 sectors/track, 365 cylinders
Units = cylinders of 1008 * 512 = 516096 bytes

   Device Boot      Start         End      Blocks  Id System
/dev/hda1               1          49       24695+ 83 Linux
/dev/hda2              50         114       32760  83 Linux
/dev/hda3             115         365      126504  83 Linux

Command (m for help): w  
The partition table has been altered.
Calling ioctl() to re-read partition table

The "w" command tells fdisk to 'write' the partitions we created in memory to the disk image; and if you use fdisk again with the "-l" (list all partitions) switch, you'll find it understands (from doing some math) that we are indeed using a geometry of only 16 heads per cylinder. (Curiously, the first time through we used a '+24M' and '+32M' which resulted in partitions having only 48 cylinders; so about 23.63 MiB, and 63 cylinders; so about 31.0 MiB, respectively. So it appeared to 'round down' on these two instead of 'up'. Thus, the reason we opted to insert the cylinder numbers instead to obtain partitions having about 24.1 MiB and 31.99 MiB, respectively.)

18. Enter the following command to view (use the Up and Down Arrow and Page keys while doing so) the contents of the ttylinux configuration file; don't worry, we'll show every step of just a handful necessary to edit and use it below (we simply wanted you to see what was in the file before using what will likely be the difficult for you to learn vi editor; the only one available on this .ISO file):

cat install.conf | less

19. Press the q (quit) key to stop viewing the file, and enter the following command (making sure you do *not* do ANYTHING ELSE except what we list below, until told otherwise!):

vi install.conf

Use the Up and Down Arrows keys in order to place the 'cursor' at the beginning of these lines:

   _y       x      x     8M    /dev/hda5  /tmp       ext2  defaults     1 1
    y       x      x     16M   /dev/hda6  /usr/local ext3  defaults     1 1
    y       x      x     16M   /dev/hda7  /var       ext3  defaults     1 1

This is 'line 50' which will appear as 50/207 in the status line at the bottom of the screen like this:

- install.conf [Modified] 50/207 24%

Press the "i" key one time (and you will be in what's called 'insert' mode; you should also see the '-' in the status line change to a capital 'I'). Type in a '#' character at the beginning of this line, then use the Left and Down Arrow keys to type another '#' character at the beginning of lines 51 and 52 like this:

   # y       x      x     8M    /dev/hda5  /tmp       ext2  defaults     1 1
   # y       x      x     16M   /dev/hda6  /usr/local ext3  defaults     1 1
   # y       x      x     16M   /dev/hda7  /var       ext3  defaults     1 1

Using the Up and Right Arrow keys, place the 'cursor' at the "64M" of line 47, and change it to "125M". NOTE: The 'delete' key will often act like a 'Backspace' key, so do what you can under that condition. The finished line should look like this:

    y       x      x     125M  /dev/hda3  /          ext3  defaults     1 1

Now if you wish, you can move down to line 70 and change the time zone (TZ) from 'MST' to whatever 3 characters you know stand for your own time zone; e.g., 'PST' is 'Pacific Standard Time'. There's no need to change anything else, since Bochs cannot easily do networking (whereas both VMWare and VirtualBox are great for connecting their virtual machines to the Internet through whatever current connection you have!).

Now press the ESC key to exit 'insert' mode, and lastly ENTER the following command wherever the 'cursor' happens to be:

:wq

The ':' key enters a special command response, 'w' tells vi to write the changes to disk and 'q' quits the vi editor. You can check on your changes using the cat command from above. If they're OK, you're ready to install ttylinux on your disk image!

20. Enter the following command at the console prompt:

ttylinux-installer --config=install.conf /dev/hdb

In the command above, '/dev/hdb' refers to the CD-ROM drive (the source); not to where we intend to install the ttylinux OS, since that's already noted in the configuration file we edited. After entering the command above, you should see the following:

# ttylinux-installer --config=install.conf /dev/hdb
Listing device partition format options:
...will format /dev/hda3 as ext3
...will format /dev/hda2 as swap
...will format /dev/hda1 as ext3
Making file systems:
-> mkfs.ext3 on /dev/hda3
-> mkswap on /dev/hda2
Setting up swapspace version 1, size = 32509952 bytes
UUID=15fb943a-9f11-4868-8c7c-8b9166982c0e
-> mkfs.ext3 on /dev/hda1
Mounting file systems:
-> mount [ext3] /dev/hda3 at /tmp/ttylinux/targt/
-> mount [ext3] /dev/hda1 at /tmp/ttylinux/targt/boot
i> Mounting ttylinux CD-ROM on /dev/hdb ... OK
i> Installing ttylinux distribution packages.
   ***** Installing ttylinux-i486-16.1
=> bash-4.2
=> busybox-1.21.0
=> dropbear-2013.58
=> e2fsprogs-1.42.7
=> glibc-2.9
=> iptables-1.4.18
=> lilo-23.2
=> ncurses-5.9
=> retawq-0.2.6c
=> thttpd-2.25b
=> ttylinux-basefs-1.0
=> ttylinux-devfs-1.0
=> ttylinux-utils-1.5
i> Installing ttylinux distribution data [/ttylinux] ... DONE
i> Copying ttylinux kernel ....... OK
i> Unmounting ttylinux CD-ROM on /dev/hdb ... OK
i> Installing LILO boot loader.
Warning: Unable to determine video adapter in use in the present system.
Warning: Video adapter does not support VESA BIOS extensions needed for
  display of 256 colors.  Boot loader will fall back to TEXT only operation.
Added ttylinux  *
2 warnings were issued.
-> umount /dev/hda1 from /tmp/ttylinux/targt/boot
-> umount /dev/hda3 from /tmp/ttylinux/targt/

i> Installation complete.

21. Use the command "shutdown -h" to shut down and halt this running Bochs emulation of the ttylinux install CD.

22. Before we boot-up the new drive image for the first time, ensure the "bochsrc.bxrc" file has been edited as follows:

boot: c
#boot: cdrom

And comment-out (put '#' character in front of) the "ata0-slave: type=cdrom, path="ttylinux-virtio_i486-16.1.iso", status=inserted" line, so it will no longer be connected -- or, perhaps wait until after your first boot-up to see if you'll need this again.

23. Start-up the Bochs Emulator again, and note whether there are any error messages. It's common for there to be some warnings about the system time. However, if you see any errors that state fsck needs to be run, you'll likely need to boot-up from the CD again. For example, on our first reboot, it stated: "/dev/hda3: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY."; which can only be corrected by running fsck while that file system is not 'mounted'; that is, you cannot fix a problem on the same file system partition you're attempting to run the program from!

More will be posted in the near future... this page is still Under Construction !!!

If you need any help in setting up the Bochs Debugger, please email us.

First Published: July 28, 2013 (28.07.13).
Last Update: July 29, 2013 (29.07.2013).

You can write to me using this: online reply form. (It opens in a new window.)

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