Pc Engine Cd Isos Download !!BETTER!!
This project is just a technical demonstration of what we can now achieveon pc engine. Don't expect it to be usable for all games, nor bigger games, etc..It's a just a proof of concept and a technical challenge that was fun to face.
Pc Engine Cd Isos Download
So, now it's more or less useable, it's publicly available for pc engine fans.Of course you shouldn't sell it, claim it's ours nor blame anyone if your dog cites Socratequotes every other minuts because of what you found here.
Without entering too much in details, here are the concepts applied here. First, thecd enabled pc engine systems have some RAM usable at runtime. This is the place wheredata coming from the cd are placed and used as code, graphics, etc... Starting fromversion 3.0 (hence Super Cd system 3.0 and the Arcade Cards), there are 2 Mega bitsavailable. This room is enough for storing a whole hucard in it, making the systemvery close of the state where a hucard is inserted in the console.
In our task, we have some luck, there's just one operation which is problematic.It's TAM, an operation which takes an argument, a field of bit, indicating thelocation in RAM where to map a physical bank (Actually, it could point atseveral locations at once, but the normal use makes such that there's only bitset at once). It uses the value of the register A to know the value of the physical bank.Well, ok, we only have to make sure that A got incremented by 0x68 before every TAM.Easy.Easy ? Not really. You can't insert an instruction in a bytecode without breakingeverything. The problem is that jumps, calls, etc... will be fooled if you insertextra data. The matter is that we can eventually alter the code but not changing thelength of instructions. Now, we have to check how the value of the register A is set.Hopefully, it's mostly loaded with a fixed value just before a TAM. That's quite aperfect situation, we can simply add 0x68 to the argument in the code and A willbe incremented of 0x68 at runtime. Sometimes, A is incremented from another valueof physical bank. If we assume we managed to catch others TAM argument, the incrementationwill retains the 0x68 offset, being a relative alteration of the argument. Still,there are a few tricky things, like values loaded dynamically from the memory wherethe location is also loaded from the memory at runtime. And eventually they arecomputation on the register A before having it used which makes this way ofdoing unusable (imagine "Load A with the physical bank at 0x4000 (normally 2), doubleA (4) and map the bank indicated by A (4) at 0x6000" with A been incremented by 0x68,the final value would be (0x68 + 2) * 2 instead of 0x68 + (2 * 2) ). On another hand,to detect the usual pattern (loading A with immediate value then apply TAM) we can onlyrely on a basic expression of 4 bytes such that 2 are fixes (opcode of the A loading andTAM), 1 is under a given value (the argument of the loading of A) and the last onlyhave one bit set. As it's not very sharp, it was easy to be fooled and "patch" pieceof data which aren't to be patched. It could lead to crashes or corruption in graphics,sound, etc...While the static approach works in a few number of case, it shows its limits.One day, by checking at pc engine internals stuff, Ben noticed that the BRK opcode,which is normally used to indicate an error but in fact is a software interruption,ie an operation which jumps to a subroutine, located via a fixed location in RAM. Butunlike usual soft interruption opcodes, it takes an argument and set the return pointof the interruption handler to the opcode after this argument, as if it was a 2-byteslong opcode. Hmm, doesn't it sounds like similar to our dear TAM opcode ? Of course.Now what, we can replace all TAM occurence by a jump to a subroutine and have an argumenthandy for our subroutine (well, in a very tricky way, but still...). As this subroutineis normally an error one, or used to debug, in games, it's unused, we can safely puta custom handler in it. What will it do ? As you may guess, it will reconstruct a TAMfrom the BRK argument using self modifying code inline and alter the value of A byadding 0x68 when needed (yes, indeed, sometimes, it references absolute, system bankwhere we shouldn't add 0x68). We then call our custom TAM and we can even restore the oldvalue of A if we want.In order to catch all relevant TAM and only them, the best way is to detect themat runtime. So, as Hu-Go! is a working GPL pc engine emulator, the best was tointegrate the code to detect TAM in it and convert all TAM opcode into BRK opcode.Before this, we had redirected statically the BRK handler to a subroutine we hadinserted in some free space (found in almost every game, the handler is just about40-50 bytes long).
The music library at Indiana University has assumed the task of indexing all the music resources on the web. The music resources index is located at /music- resources.html. By pointing your World Wide Web browser at this excellent index, you can navigate through a wealth of musical treasures. For example, the Classics World web site ( ) lets you browse the latest releases of classical music on CD-ROMS. At the World Wide Web's Classical Music MIDI Archives ( ) you can download and play MIDI files for thousands of classical music compositions. The artist-specific index at lists hundreds of performing musicians who have established World Wide Web sites.
If it required fancy tools and advanced skills to put music scholarship on the World Wide Web, it would not be feasible to issue the call for action that I am about to make. Happily, the same tools that are used to author the materials -- word processors such as Microsoft Word and WordPerfect -- an create web pages. Microsoft gives away for free the Internet Assistant add-on to Microsoft Word; you can download it from WordPerfect for Windows users can create web pages with WP Internet Publisher, which is also free; you can download it from
When everyday word processing tools -- the same tools used to create scholarly documents in the first place -- become the tools for creating World Wide Web documents, there is no excuse for not getting down to work and putting music scholarship onto the World Wide Web. The musical community is lagging behind other disciplines, and I call upon the College Music Society to help music scholars get organized and take advantage of the Internet. Let's help all music scholars get their materials onto the web, connect these materials into the World Wide Web search engines, and create a fascinating future for music scholarship.
STATE DEPARTMENT FOREIGN AFFAIRS NETWORK....( ) The Bosnia link provides full text of speeches,briefings and documents on the Balkans. The DOSFAN gopher can be searched by key word... e.g. search on"Cambodia" to get the US policy and an overview of the issues as seen by senior State Officials.The Regional Bureaus provide copies of congressional testimony and speeches by Under andAsst. Secretaries; the publications directory includes the full set of Human RightsReports (a real gold mine of background information), economic reports and copies of DISPATCH the State Departmentweekly magazine for Foreign Service Officers with good info on foreign policy. DISPATCH is available as a textfile or as a .PDF file (compressed image viewable with ADOBE ACROBAT which can be downloaded for free fromthe NY TIMES FAX pagebelow).
NEW YORK TIMESFAX ( ) A daily 8 pagenews, business, sports and crossword puzzle extract from NYT. Files are about 100K and requires that youhave ADOBE ACROBATwhich can be downloaded (1.5MByte) from the Times server.
THAILAND, LAOS, BURMA AND CAMBODIA NEWS ARCHIVES...( ) Archives of the soc.culture.thai,Laos, Burma and Cambodia newsgroups. While there is lots of garbage there are also lots ofnews reports from Reuters, AP, Asahi News, Bangkok Post, LA Times NY Times and Wall Street Journal that people have downloaded and posted(illegally no doubt). Good Stuff to look at as you transit the SCS.
NAVY SERVERS.... ( ) Pointers to Navyservers of all types. Tends to be heavy on the research labs and engineering centers asyou might expect. The Public Affairs servers has a searchable database of Navy Newsreports going back several years which the PAO can occasionally find useful. 350c69d7ab