Dodgy hardware mod maker
- Jul 8, 2003
- New Zealand
This is just a suggestion! I think it's a good idea to have a fixed format so that (for example) app launchers or file managers can display metadata about the files on SD. Inside Linux things are already defined, this is for apps that run outside of Linux.
GP2X "Open Executable" format (name thanks to DJWillis) - filename extension is ".g2x" - executable files go in "/GP2XBIN" - game data files go in "/GP2XGAME/<gamename>" - all data is little-endian Base is 0x00008000 Contents of executable file: Address 0x00008000 4 bytes Jump to start code 0x00008004 4 bytes Header version. Will start at zero and increase willy-nilly :) 0x00008008 4 bytes Address of start of bss section 0x0000800C 4 bytes Address of end of bss section (if start and end of bss are the same, then don't clear anything) 0x00008010 4 bytes Address of start of data section 0x00008014 4 bytes Address of end of data section (if start and end of data are the same, then there is no data section) 0x00008018 32 bytes Application name 0x00008038 32 bytes Application author 0x00008058 32 bytes Application description 0x00008078 4 bytes Application version bits 31-24 are major version bits 23-16 are minor version bits 15-0 are build number So version is "1.2.3456" sort of thing 0x0000807C 4 bytes bits 31-16 are number of frames in application icon animation (1 for a still image) (if this number is zero, then there is no application icon and the loader should display a default) bits 15-0 are animation speed, milliseconds per frame (a value of zero means 65536 ms/frame) 0x00008080 2048 bytes 32x32, 16-bit hicolour application icon As many icons are included as there are frames in the animation 0x??????80 xxxx bytes application code stack can go at the top of RAM, perhaps backed off a bit so that a stack underflow won't immediately cause a crash... say, 0x03FF F000 (4k down from the top of RAM).