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Catalogue of Arcade Emulation Software - the Absolute Reference

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X-Arcade

X-Arcade

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alg.c

0.110u5 [Aaron Giles]


NOTES:

- Hardware: American Laser Game = Amiga 500 + SONY LDP1450 Laser Disc player

- Games Supported: Mad Dog McCree [3 versions], Who Shot Johnny Rock? [2 versions], Mad Dog II: The Lost Gold [2 versions], Space Pirates, Gallagher's Gallery, Crime Patrol, Crime Patrol 2: Drug Wars [2 versions], The Last Bounty Hunter, Fast Draw Showdown, Platoon and Zorton Brothers (Los Justicieros).


WIP:

- 0.113u2: Changed VSync to 59.970000 Hz.

- 0.111u6: Ernesto Corvi fixed the data fetch and scrolling calculation for almost all video modes in the Amiga driver.

- 0.111u5: Nathan Woods updated the Amiga video driver to use the new BITMAP_ADDR* macros instead of using the line[] array. Added Custom sound.

- 0.111u4: Ernesto Corvi fixed system time counters in the Amiga code. Changed VSync to 59.970001 Hz.

- 0.111u3: More updates to the laserdisc emulation, based on more complete understanding of how the discs are encoded and how they will eventually be stored [Aaron Giles]. Another Amiga update [Ernesto Corvi]: Fixed blitter in line mode. Modified Copper to run on odd memory bus cycles. Fixed screen delay offset when display data fetch is not word aligned.

- 0.111u2: Amiga core system updates [Ernesto Corvi]: Updated 6526/8520 CIA to be able to set the value of the SP pin. This is needed to emulate the Amiga keyboard. Updated the custom chips emulation to delay for about 24 cycles the issuing of interrupts after a write to INTENA or INTREQ. Fixed a bug where if INTREQ got cleared programatically, it would 'forget' about pending CIA interrupts, causing the CIA to stop sending further interrupts. Fixed the interrupt delay logic. Now it properly delays firing the irqs, not the masking/disabling. Fixed return value for unused/invalid custom registers reads. Added Denise ID custom register to properly identify OCS, ECS and AGA. Added reset to custom, autoconfig and cia when a RESET opcode is found. Resetting the custom chips will now clear INTENA, preventing further interrupts. Fixed a bug in the RBF interrupt request code check. Fixed a bug on the 6526/8520 CIA that prevented chained counters from working. Added support for the 'blitter-nasty' bit on the blitter. Fixes many games that displayed wrong graphics.

- 2nd January 2007: Aaron Giles - Some Laserdisc Progress: After a bit of a hiatus with the holidays and fun power outages, I've been back making some progress on the laserdisc support. I now have the basic CHD format spec'ed out and implemented. And I have modified chdman.exe to support two new commands: -createav, which takes an AVI file plus an optional metadata file and compresses them to a CHD; and -extractav, which takes a CHD file and extracts it to an AVI file and a metadata file. (And yes, the AVI reader/writer is cross-platform code, so it will work on non-Windows platforms as well. I also have a mostly complete QuickTime reader/writer, but am not sure if it is worth the effort to complete it. Though plugging the two together would produce an AVI <-> QuickTime conversion program, which would be useful!). I'm happy to say that with a little bit of work using a test capture, I am now actually capable of displaying video from within MAME. There's still a lot of work to do yet to get the rest of the way, but this is a good step forward. Next up will be synchronizing frame and track numbers (you'll note the numerical discrepancy in the screenshot), wiring up the sound, improving performance, further enhancing chdman.exe with some additional I/O options, and all the while working with the great group of folks I've been talking to in order to get great quality source captures. More to come as it all comes together!

- 0.110u5: Reorganized the laserdisc support a bit to accommodate new players. Added Sony LDP-1450 support.


Going up to lossy with medium deltas (up to 4/256 per component) gets you closer to 4:1 and 5:1 compression with almost no visible difference. Increasing the max deltas beyond that helps further with compression, but it definitely starts to become visible. Not everything is nailed down yet, and it will probably take a couple of months to materialize, but those are the basics. The first game I'm looking at is obviously Dragon's Lair, but coincidentally, I just received in the mail a driver for the American Laser Games series (http://www.dragons-lair-project.com/tech/pages/alg.asp) of shooters as well, which were all run on an Amiga 500 with a genlock. Fortunately, the Amiga emulation is pretty decent these days, so things are progressing well there. Now that the basic system is up and running, I'm hoping others can help get the rest of the laser games moving forward. In 0.110u4 I included support for a couple of common laserdisc players. Even though you can't see any video yet, you can at least watch their operation to see if things are working properly. In 0.110u5 I'll have support for the Sony LDP-1450 (http://www.dragons-lair-project.com/tech/ldguide/sony.asp) laserdisc player and the ability to display dummy frames (each frame is solid color and gets a unique Cb/Cr value) so that you get a little better sense of the operation. And hopefully in the next month or so, I'll have the first video running at last...