This is yet another Megadrive / Genesis / Sega CD / Mega CD / 32X / SMS
emulator, which was originally written having ARM-based handheld devices
in mind, but later had got various improvements for other architectures
too, like SH2 recompilers for MIPS (mips32r2), ARM64 (armv8), RISC-V (RV64IM)
and PowerPC (G4/2.03).

PicoDrive was the first emulator ever to properly emulate Virtua Racing and
it's SVP chip.

Currently the main development happens in the
[irixxxx's fork](https://github.com/irixxxx/picodrive),
[notaz's repo](https://github.com/notaz/picodrive) isn't updated as much.

### compiling

A list of platforms for which this is possible can be obtained with

> configure --help

If you want to build an executable for a unixoid platform not listed in the
platform list, just use

> configure --platform=generic

If DRC is available for the platform, it should be enabled automatically.

For other platforms using a cross-compiling toolchain I used this,
assuming $TC points to the appropriate cross compile toolchain directory:

platform|toolchain|configure command
--------|---------|-----------------
gp2x,wiz,caanoo|open2x|CROSS_COMPILE=arm-open2x-linux- CFLAGS="-I$TC/gcc-4.1.1-glibc-2.3.6/arm-open2x-linux/include" LDFLAGS="--sysroot $TC/gcc-4.1.1-glibc-2.3.6/arm-open2x-linux -L$TC/gcc-4.1.1-glibc-2.3.6/arm-open2x-linux/lib" ./configure --platform=gp2x
gp2x,wiz,caanoo|open2x with ubuntu arm gcc 4.7|CROSS_COMPILE=arm-linux-gnueabi- CFLAGS="-I$TC/gcc-4.1.1-glibc-2.3.6/arm-open2x-linux/include" LDFLAGS="-B$TC/gcc-4.1.1-glibc-2.3.6/lib/gcc/arm-open2x-linux/4.1.1 -B$TC/gcc-4.1.1-glibc-2.3.6/arm-open2x-linux/lib -L$TC/gcc-4.1.1-glibc-2.3.6/arm-open2x-linux/lib" ./configure --platform=gp2x
dingux|dingux|CROSS_COMPILE=mipsel-linux- CFLAGS="-I$TC/usr/include -I$TC/usr/include/SDL" LDFLAGS="--sysroot $TC -L$TC/lib" ./configure --platform=dingux
dingux|dingux with ubuntu mips gcc 5.4|CROSS_COMPILE=mipsel-linux-gnu- CFLAGS="-I$TC/usr/include -I$TC/usr/include/SDL" LDFLAGS="-B$TC/usr/lib -B$TC/lib -Wl,-rpath-link=$TC/usr/lib -Wl,-rpath-link=$TC/lib" ./configure --platform=dingux
retrofw|retrofw|CROSS_COMPILE=mipsel-linux- CFLAGS="-I $TC/include -I $TC/include/SDL -Wno-unused-result" LDFLAGS="--sysroot $TC/mipsel-buildroot-linux-uclibc/sysroot" ./configure --platform=retrofw
gcw0|gcw0|CROSS_COMPILE=mipsel-gcw0-linux-uclibc- CFLAGS="-I$TC/usr/mipsel-gcw0-linux-uclibc/sysroot/usr/include -I$TC/usr/mipsel-gcw0-linux-uclibc/sysroot/usr/include/SDL" LDFLAGS="--sysroot $TC/usr/mipsel-gcw0-linux-uclibc/sysroot" ./configure --platform=gcw0
rg350|rg350|CROSS_COMPILE=mipsel-linux- CFLAGS="-I$TC/usr/include -I$TC/usr/include/SDL" LDFLAGS="--sysroot $TC -L$TC/lib" ./configure --platform=rg350
miyoo|miyoo|CROSS_COMPILE=arm-miyoo-linux-uclibcgnueabi- CFLAGS="-I$TC/arm-miyoo-linux-uclibcgnueabi/sysroot/usr/include -I$TC/arm-miyoo-linux-uclibcgnueabi/sysroot/usr/include/SDL" LDFLAGS="--sysroot $TC/arm-miyoo-linux-uclibcgnueabi/sysroot" ./configure --platform=miyoo

For gp2x, wiz, and caanoo you may need to compile libpng first.

After configure, compile with

> make

### helix MP3 decoder for ARM

For 32 bit ARM platforms, there is the possibility to compile the helix MP3
decoder into a shared library to be able to use MP3 audio files with CD games.
The helix source files aren't supplied because of licensing issues. However, if
you have obtained the sources, put them into the platform/common/helix
directory, set CROSS to your cross compiler prefix (e.g. arm-linux-gnueabi-)
and LIBGCC to your cross compiler's libgcc.a
(e.g. /usr/lib/gcc-cross/arm-linux-gnueabi/4.7/libgcc.a), and compile with

> make -C platform/common/helix CROSS=$CROSS LIBGCC=$LIBGCC

Copy the resulting ${CROSS}helix_mp3.so as libhelix.so to the directory where
the PicoDrive binary is.

### installing

You need to install the resulting binary onto your device manually.
For opendingux, gcw0, and rg350, copy the opk to your SD card.
For gp2x, wiz, and caanoo, the easiest way is to unpack
[PicoDrive_191.zip](http://notaz.gp2x.de/releases/PicoDrive/PicoDrive_191.zip)
on your SD card and replace the PicoDrive binary.
For legacy dingux, unpack the dge zip and copy the files to your SD card.

Send bug reports, fixes etc to <derkub@gmail.com>