I have written a Z80 target for QEMU (an emulator using dynamic recompilation), mainly as a learning exercise. It currently emulates the 48K ZX Spectrum.
To build it, you will first need to apply
a
patch to the QEMU source (from CVS). After applying the patch, you will
need to place a copy of the 48K ZX Spectrum ROM in the
pc-bios directory. If you only wish to compile the Z80 target,
you will save time when compiling if you pass
‘--target-list=z80-softmmu’ to the configure
script.
To boot the emulator, you'll first need to create a test disk image. (This
is a requirement of QEMU that I'll try to remove later.) To do this, run
‘qemu-img create hda.img 1M’. You can now boot the
system using ‘qemu-system-z80 -hda hda.img’.
Alternatively, depending on your OS, you may be able to run
‘qemu-system-z80 -hda /dev/null’, or some equivalent
command.
Note that if you modify some of the files in the target-z80,
directory, make misses some dependencies, so you'll have to run
make clean. In particular, if you alter CPUZ80State
and forget to run make clean, you may find that the build appears
to be successful, but qemu-system-z80 crashes. Please send
patches to the address given below!
Many thanks to those on #spin that helped me with some of the debugging! Thanks also to Ulrich Hecht for the improved version of the patch.
An older version that applies to QEMU 0.9.0 is also available.
Stuart Brady