Release notes:

Latest release with changes as from included readme-psp.txt:
PSP MAME4ALL v4.9r1 Hires by TTYman, 05/11/2007
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Install directions:
– Copy in /PSP/GAME (firmware 1.5) or /PSP/GAME150 (firmware 1.5 compatibility for 3.xx OE release);
There are three different builds in archive:
1) PSP-100x (psp_mame4all_v4.9r1);
2) PSP-100x without neogeo and cps1 support (psp_mame4all_v4.9r1-fat-noneogeo-nocps1);
3) PSP-200x (psp_mame4all_v4.9r1-slim);
Use psp_mame4all_v4.9r1 as installation base, then replace EBOOT.PBP with your needed/preferred build;
– Recreate zipped roms with included ClrMame compatible .DAT files (v0.34-v0.36 mixed roms);
– Add created zipped roms files in ROMs subfolder and samples in samples subfolder;
Samples must be in .sam old Mame pre-v0.35 format, downloadable from http://www.mameworld.net/samples/sam.htm
Specific Features:
– Based on latest GP2X MAME4All release v4.9;
– 480×272 full PSP Hires Support, now games with >320 orizz. and >240 vert. pixels are fully playable (Loderun, Galaga etc.);
– Overclock support, from 133 to 333 MHz;
– Fixed, Fixed Divided by 2, Software Scaled and Software Full Screen Stretched resolutions (all maximum 480×272);
– Frameskip as GP2X version (fixed 0-5, auto 1-5);
– Vsync on/off;
– Save configuration support, default and per game;
– 22KHz with 16 voices predefined sounds, 33KHz and 44KHz frequencies with 4, 8 and 16 voices combinations added;
– Preliminary analog support;
– Autocentering fix for all resolutions;
– Optimized compiled code as derived from GP2X version, but for PSP cpu (fastest graphics core!);
– Stripped & Packed executable, only 2.1MB;
– Original graphics theme from Gold edition;
– Music in menu (filename music.psp in data folder), in these supported formats: .MOD, .S3M, .IT, .XM and .OGG;
– Added, as bonus, 1st classified OldSkool at Assembly 2007 Music Competition (Commodore 64 based), in .OGG format;
– Graphic theme 480×272 BMP skins support, both pspmenu480.bmp and pspsplash480.bmp in folder skins;
Specific Controls:
– Button SELECT: Insert credits.
– Button START: Play.
– Button HOME: after Pause exit game and return to menu.
– Buttons L+R: Activate/deactivate screen fixed/fixed div2/scale/stretch.
– Buttons L+R pressed during one second: Pause.
– Buttons L+HOME simultaneously: Reset emulation.
Fixed from 4.7r3 (same as 4.8r1 unreleased)
– Crash when sampled used.
– Unified builds, thanks to new Z80 core, Mame 0.53 based, compatible with system16, neogeo and classic roms.
– Implemented PSP-2000 (slim) specific support, so double memory available to load roms, thanks to keiich-san code.
Fixed from 4.7r2:
– Sounds now are near arcade perfect, with minor gliches in some sound chips emulations;
– Gold (CPS1, System16 and Neogeo) specific emulations are now stand-alone, as require different z80 cpu implementation;
– Improved performance with sounds, oldies with 0 frame skip and vsync on, others with auto-1 and auto-2;
Fixed from 4.7:
– 133 MHz in menu and while paused, for battery saving;
– VSync really works now;
– Corrected build configuration and Makefile, so sounds in various games are now back;
– Correct fixed, div2, sw scaled and sw stretched resolutions, with autocentering;
Known Problems:
– General audio with some gliches due to original unoptimized threaded sound core;
– Preliminary Analog stick support doesn’t recognize very fast movements;
– No rotate support;
PSP MAME4ALL v4.9r1 Hires zipped archive (6.792.731 bytes)
PSP MAME4ALL v4.9r1 Hires zipped archive MD5 checksum file
Source code can be downloaded from official Franxis’s GP2X port, at http://www.talfi.net/gp32_franxis/.
TTYman 😉

http://ttyman.free.fr/?p=14