[About]\r
This is yet another Megadrive / Genesis / Sega CD / Mega CD emulator, which was written having ARM-based handheld devices in mind (such as PDAs, smartphones and handheld consoles like GP2X of course). The critical parts (renderer, 68K and Z80 cpu interpreters) and some other random code is written in ARM asm, other code is C. The base code originates from Dave's (fdave, finalburn) PicoDrive 0.30 for Pocket PC. The Sega/Mega CD code is roughly based on Stephane Dallongeville's Gens.\r
\r
+PicoDrive is the first emulator ever to properly emulate Virtua Racing and it's SVP chip.\r
+\r
\r
For help / comments / questions visit GP32X boards at:\r
http://www.gp32x.com/board/\r
13. "Confirm savestate"\r
Allows to enable confirmation on savestate saving (to prevent savestate overwrites), on loading (to prevent destroying current game progress), and on both or none.\r
\r
-14. "GP2X CPU clocks"\r
+14. "Save slot"\r
+This is a slot number to use for savestates. This can also be configured to be changed with a button (see "key configuration").\r
+\r
+15. "GP2X CPU clocks"\r
Here you can change clocks of both GP2X's CPUs. Larger values increase performance. There is no separate option for the second CPU because both CPUs use the same clock source. Setting this option to 200 will cause PicoDrive NOT to change GP2X's clocks at all (this is if you use external program to set clock).\r
\r
-15. "[Sega/Mega CD options]"\r
+16. "[Sega/Mega CD options]"\r
Enters Sega/Mega CD options menu (see below).\r
\r
-16. "[advanced options]"\r
+17. "[advanced options]"\r
Enters advanced options menu (see below).\r
\r
-17. "Save cfg as default"\r
+18. "Save cfg as default"\r
If you save your config here it will be loaded on next ROM load, but only if there is no game specific config saved (which will be loaded in that case).\r
\r
-18. "Save cfg for current game only"\r
+19. "Save cfg for current game only"\r
Whenever you load current ROM again these settings will be loaded (squidgehack and RAM settings will not take effect until emulator is restarted).\r
\r
\r
1. "Gamma correction"\r
Alters image gamma through GP2X hardware. Larger values make image to look brighter, lower - darker (default is 1.0).\r
\r
-2. "Emulate Z80"\r
+2. "A_SN's gamma curve"\r
+If this is enabled, different gamma adjustment method will be used (suggested by A_SN from gp32x boards). Basically it makes difference for dark and bright colors.\r
+\r
+3. "Perfect vsync"\r
+This one adjusts the LCD refresh rate to better match game's refresh rate and starts synchronizing rendering with it. Should make scrolling smoother and eliminate tearing.\r
+\r
+4. "Emulate Z80"\r
Enables emulation of Z80 chip, which was mostly used to drive the other sound chips. Some games do complex sync with it, so you must enable it even if you don't use sound to be able to play them.\r
\r
-3. "Emulate YM2612 (FM)"\r
+5. "Emulate YM2612 (FM)"\r
This enables emulation of six-channel FM sound synthesizer chip, which was used to produce sound effects and music.\r
\r
-4. "Emulate SN76496 (PSG)"\r
+6. "Emulate SN76496 (PSG)"\r
This enables emulation of additional sound chip for additional effects.\r
\r
Note: if you change sound settings AFTER loading a ROM, you may need to reset game to get sound. This is because most games initialize sound chips on startup, and this data is lost when sound chips are being enabled/disabled.\r
\r
-5. "gzip savestates"\r
+7. "gzip savestates"\r
This will always apply gzip compression on your savestates, allowing you to save some space and load/save time.\r
\r
-6. "Don't save last used ROM"\r
+8. "Don't save last used ROM"\r
This will disable writing last used ROM to config on exit (what might cause SD card corruption according to DaveC).\r
\r
-7. "craigix's RAM timings"\r
+9. "craigix's RAM timings"\r
This overclocks the GP2X RAM chips, but may cause instability. Recommended if you use the second core for sound. Needs emulator restart to take effect.\r
See this thread:\r
http://www.gp32x.com/board/index.php?showtopic=32319\r
\r
-8. "squidgehack"\r
+10. "squidgehack"\r
Well known way to improve the GP2X performance. You must restart the emulator for the change of this option to take effect.\r
\r
\r
This enables 8 channel PCM sound source. It is required for some games to run, because they monitor state of this audio chip.\r
\r
7. "ReadAhead buffer"\r
-This option is for dealing with slow SD card access in GP2X, which makes FMV games unplayable. It will allow emulator not to access SD card for longer periods of time, but it will take more time to fill the buffer.\r
+This option can prefetch more data from the CD image then requested by game (to avoid accessing card later), what can improve performance in some cases.\r
+"OFF" is the recommended setting.\r
\r
8. "Save RAM cart"\r
Here you can enable 64K RAM cart. Format it in BIOS if you do.\r
Key configuration\r
-----------------\r
\r
-When you select "Configure controls" from the menu, you enter a key configuration mode, where you use SELECT to change an action, and then press a key you like to bind to that action. You can press the same key again to unbind. Select "DONE" action and press any key to finish.\r
+Select "Configure controls" from the main menu. Then select "Player 1" and you will see two columns. The left column lists names of Genesis/MD controller buttons, and the right GP2X ones, which are assigned to them. If you bind 2 different GP2X buttons to the same action, you will get a combo (which means that you will have to press both buttons for that action to happen.\r
\r
\r
[Other important stuff]\r
VDP: yes, except some quirks not used by games\r
YM2612 FM: yes, optimized MAME core\r
SN76489 PSG: yes, MAME core\r
+SVP chip: yes! This is first emu to ever do this.\r
+Some in-cart mappers are supported too.\r
\r
Sega/Mega CD:\r
another 68k @ 12.5MHz: yes, Cyclone too\r
\r
\r
[Problems / limitations]\r
-* 32x and SVP are not emulated.\r
+* 32x is not emulated.\r
* Various VDP quirks (window bug, scroll size 2, etc.) are not emulated, as very few games use this (if any at all).\r
-* Some games don't work or have glitches because of inaccurate timing and sync between the emulated chips.\r
+* The emulator is not 100% accurate, so some things may not work as expected.\r
\r
\r
[Credits]\r
* Hermes PS2R, god_at_hell for the CpuCtrl library.\r
* craigix for supplying the GP2X hardware and making this port possible.\r
* Alex for the icon.\r
+* Exophase and Rokas for various ideas.\r
* Anyone else I forgot. You know who you are.\r
\r
\r
notaz.gp2x.de / picodrive.git / blobdiff