= QEMU =


You can run RTEMS in the open source processor emulator [http://fabrice.bellard.free.fr/qemu/ QEMU]. The QEMU emulator runs on a number of hosts including Linux and Windows. It also supports a number of [http://fabrice.bellard.free.fr/qemu/status.html processors].
= QEMU On Windows =


Install the RTEMS [wiki:TBR/UserManual/MinGW_Tools_for_Windows MinGW Tools for Windows]. Download the processor emulator you wish to use and install. For example we will install the i368 emulator to '''c:\rtems\i386\qemu-0.8.2-windows'''. Download the boot floppy image [ftp://ftp.rtems.org/pub/rtems/qemu/i386-pc/rtems-boot.img] to '''c:\rtems\i386'''. To run QEMU create the batch file '''c:\rtems\i386\qemu.bat''' with:

 rem @echo off
 set QEMU=C:\rtems\i386\qemu-0.8.2-windows
 %QEMU%\qemu -L %QEMU% -m 128 -boot a -fda c:\rtems\i386\rtems-boot.img -hda fat:%1

The boot floppy will look in the root directory the QEMU C: drive for a file called '''rtems-grub.cfg'''. The QEMU C: is a directory on your hard disk passed to QEMU on its command line and can be seen in the '''qemu.bat''' file we created as the '''-hda fat:%1''' option. The command line option we pass to '''qemu.bat''' is a directory that is the root directory the QEMU C: drive. For example download and build RTEMS for the i386 target as described on the [wiki:TBR/UserManual/MinGW_Tools_for_Windows MinGW Tools for Windows] page. Then install [ftp://ftp.rtems.org/pub/rtems/qemu/i386-pc/rtems-grub.cfg rtems-grub.cfg] into the '''c:\rtems\src\i386\i386-rtems4.7\c\pc586\testsuites\samples''' directory. Open the '''RTEMS (i386)''' command window by running '''c:\rtems\i386\rtems-cmd.bat''' then enter:

 RTEMS(i386) C:\rtems\i386>qemu c:\rtems\src\i386\i386-rtems4.7\c\pc586\testsuites\samples

The QEMU windows will open and GRUB will provide you with a menu of the RTEMS sample applications. Select an application and watch it run.
= QEMU PC (i386) Emulator =


The RTEMS PC BSP runs in the QEMU emulator. The QEMU emulator needs a boot image that will load RTEMS and we use GRUB for this. The simplest may to do this is to create a floppy disk image and tell QEMU to boot from a floppy disk.
= Making a Boot Floppy Disk =


We run RTEMS in QEMU by first booting from a floppy disk image containing the GRUB boot loader. You can use the image we have made by downloading it from the RTEMS ftp server. The following instructions built the image and were run on a Fedora Core 5 Linux host.

Download the latest release of version 2 the [http://grub.enbug.org/FrontPage Grub boot loader] from [ftp://alpha.gnu.org/gnu/grub/]. Build the package with the following configure command:

  $ ../grub-1.94/configure --prefix=/tmp/g2/build
  $ make all install

where the prefix can be anything suitable for your machine. If configure fails with a missing LZO library check you have the lzo-devel package installed.

To make the floppy image follow the instructions in the Grub Wiki at http://grub.enbug.org/TestingOnX86. This script is adapted from the instructions:

 #! /bin/sh -x
 grub=/tmp/g2/build
 workspace=/tmp/g2
 mnt=$workspace/mnt/loop
 file=$workspace/rtems-boot.img
 export PATH=$grub/bin:$grub/sbin:$PATH
 mkdir -p $workspace
 cd $workspace
 grub-mkimage -o core.img _chain ls pc multiboot gpt fat boot reboot configfile cat help
 dd if=/dev/zero of=$file bs=512 count=2880
 /sbin/mkdosfs $file
 mkdir -p $mnt
 mount -o loop -t vfat $file $mnt
 mkdir -p $mnt/boot/grub
 cp $grub/lib/grub/i386-pc/boot.img core.img $grub/lib/grub/i386-pc/*.mod $mnt/boot/grub
 cat "configfile (hd0,0)/rtems-grub.cfg" > $mnt/boot/grub/grub.cfg
 echo '(fd0)' $file > tmp_device.map
 grub-setup -d $mnt/boot/grub -r '(fd0)' -m tmp_device.map '(fd0)'
 rm -f tmp_device.map
 umount $mnt

The default '''grub.cfg''' file will attempt to read a GRUB configuration file called '''rtems-grub.cfg''' from the root directory of the harddisk. This lets you create a specific GRUB configuration for you testing without needing to rebuild the floppy image. An example configuration that lets you run the RTEMS Samples is:

 # RTEMS Grub configuration for the Samples
 
 set default=0
 
 menuentry "RTEMS - Hello" {
  set root=(hd0,0)
  multiboot (hd0,0)/hello/hello.exe
 }
 
 menuentry "RTEMS - Ticker" {
  set root=(hd0,0)
  multiboot (hd0,0)/ticker/ticker.exe
 }
 
 menuentry "RTEMS - Minimum" {
  set root=(hd0,0)
  multiboot (hd0,0)/minimum/minimum.exe
 }
 
 menuentry "RTEMS - Paranoia" {
  set root=(hd0,0)
  multiboot (hd0,0)/paranoia/paranoia.exe
 }
 
 menuentry "RTEMS - File IO" {
  set root=(hd0,0)
  multiboot (hd0,0)/fileio/fileio.exe
 }
 
 menuentry "RTEMS - Unlimited" {
  set root=(hd0,0)
  multiboot (hd0,0)/unlimited/unlimited.exe
 }
 
 menuentry "RTEMS - Loopback" {
  set root=(hd0,0)
  multiboot (hd0,0)/loopback/loopback.exe
 }
 
 menuentry "RTEMS - PPPD" {
  set root=(hd0,0)
  multiboot (hd0,0)/pppd/pppd.exe
 }
  
 menuentry "RTEMS - Base Mulitprocessor" {
  set root=(hd0,0)
  multiboot (hd0,0)/base_mp/base_mp.exe
 }
 
 menuentry "RTEMS - Base Single Processor" {
  set root=(hd0,0)
  multiboot (hd0,0)/base_sp/base_sp.exe
 }
 
 menuentry "RTEMS - C++ Static Constructors" {
  set root=(hd0,0)
  multiboot (hd0,0)/cdtest/cdtest.exe
 }
 
 menuentry "RTEMS - C++ IO Streams" {
  set root=(hd0,0)
  multiboot (hd0,0)/iostream/iostream.exe
 }