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Text File | 1997-05-18 | 24.8 KB | 560 lines

THE ULTIMATE WAVEBLASTER (TM) TO AMIGA GUIDE V1.1 - 7. May 1997 --------------------------------------------------------------- How to connect mindblasting PC soundcards to your Amiga. Written by Christian Buchner, flowerp@eikon.e-technik.tu-muenchen.de (Please retry if my EMail host is down). History: -Revised 23. Oct. 1996, 24. Oct. 1996 -First released in comp.sys.amiga.audio 24. Oct. 1996 -released on Aminet in hard/hack 24. Oct. 1996 -added some more clarifications and tips 7. May 1997 -translated into German 7. May 1997 -upload to Aminet on 15. May 1997 Okay, guys! You wanted it, now you get it. This is how to build an interface for PC wavetable sound cards to your Amiga. It is very easy and requires very few electronic components. I am not giving any exact board layout. This documentation just describes the pinout of the sound card and all the required components. I can also give you hints and clues on how to build the interface. Anything else is up to you. You can not use any PC wavetable sound card. Any boards that use the PC ISA or PCI slots will not work. You can only use wavetable expansion boards that have a Waveblaster (TM) compatible interface. The waveblaster interface can be found on many PC soundcards (e.g. Soundblaster AWE32, not the value editions). So you can only use these wavetable boards that also fit on the AWE32. This hardware hack is basically about building a Waveblaster (TM) compatible hardware interface. And that is quite easy. For doing this hack, you _should_ have some basic knowledge about electronics. And it will be a great advantage if you have ever soldered some electronic circuitry before in your life ;-) The serial port will (optionally) stay free for external MIDI interfaces and modems. However you cannot play MIDI files and use your modem at the same time! Also mind that the modem will "mirror" any MIDI signals back into the computer (AT command mode). So it might be better to turn it off before using MIDI software. It may also happen that your modem tries to interpret the MIDI data. Mine doesn't (most of the time) because the data is sent at 31250 baud, which is not an accepted DTE rate for a modem. You could also use the serial port of any I/O extender card. But please note that _most_ of the Amiga MIDI software does not permit you to select a device driver for MIDI output. Even worse, some software directly accesses the serial port hardware. So usage of the internal serial port is highly recommended. Why using a PC MIDI sound card? ------------------------------- * Well, the Amiga has only 4 voices. * The Amiga cannot not create true HIFI sound. * When you try to obtain a higher polyphony with the Amiga's internal sound capabilities you have to use a lot of CPU power for channel mixing. * Good Amiga sounds (e.g. sound modules) require a lot of hard disk space. * External MIDI synths are expensive * and require you to buy a MIDI interface first What if I told you that modern PC wavetable sound cards are a) usually very cheap b) of a high quality c) having lots of DSP-effects d) easily to interface and e) easily usable with _your_ Amiga! It all started when a friend of mine bought a YAMAHA DB50XG wavetable board for his PC. He showed it to me and I listened. And I was amazed. The sound card played music in a quality that really sounded as if it came right out of the radio. Details about the YAMAHA DB50XG sound card ------------------------------------------ First the price here in Germany is very exciting. It is just DM199.- in some computer stores. It may, however be somewhat more expensive in your country or region. The DB50XG has often been chosen to be the best MIDI upgrade board from many similar products at comparative tests in different computer magazines. It has 4MB of wavetable ROM. It supports the General MIDI standard, of course. And it offers two standardized extensions to General MIDI. One is the TG300 mode (which is mostly compatible to Roland GS, in fact it even understands many Roland GS SysEx messages). The other mode is the Yamaha XG mode. This is excactly compatible to the external YAMAHA MU50 and MU80 MIDI expanders. From my point of view, the XG mode is really a breakthrough in MIDI technology. The polyphony is 32 notes maximum. It can play up to 16 different instruments at the same time. Voice allocation is dynamic. There are 676 different wavetable sounds. In XG mode you can access 480 voices and 11 drum kits (with 202 different sounds). In TG300B mode you have 579 voices and 10 drum kits (with 173 different sounds). The most exciting part is the DSP effect section. It allows up to 3 independent and editable DSP effects at the same time. There are 11 types of Hall, 11 types of Chorus effects and 42 variation effects. All these effects have parameters that can be changed in real time. Some exciting things are e.g a Phaser effect, a distortion effect, flanger, Rotary Speaker, Equalizer, EQ filters, Wah-Wah and many more. The sound card comes with a demo CD that contains CD audio tracks and the same tracks in form of MIDI files. You also get a documentation on 60 pages (german, english, francais) that contains tables with all instruments, drum kits, effects and SysEx messages. The sound that this card produces is in no way comparable to the "old" Amiga sound. In fact I never want to listen to any sound modules any more (-> Trashcan!). What you get is HIFI sound. You can make professional music with this board. It is in fact the same technology that is used in external MIDI expanders. And it is compatible to this equipment (MU50, MU80). You get a lot of XG midi files in the Internet. And of course you can also listen to all GS or GM midi files. Usually XG files sound better, but don't take this for granted. The pinout of the Waveblaster cards ----------------------------------- This hack will only work with PC wavetable upgrade boards that have a WaveBlaster (TM) compatible connector. This is a 26 pin dual row connector. These wavetable upgrade boards are usually mounted on a SoundBlaster (TM) or compatible sound card. This is the complete pinout of Waveblaster (TM) compatible sound cards. I found it on the UK web server of YAMAHA (www.yamaha.co.uk) in the XG FAQ file. However the pinout given there was incomplete (missing pin 26) and the audio lines were reversed. I can not guarantee that this pinout is also valid for different sound cards than the Yamaha DB50XG. / 1 2 Better leave pins without | 3 4 MIDI In any description unconnected! digital | 5 6 +5V GND | 7 8 MIDI Out | 9 10 +5V \ 11 12 13 14 +5V / 15 16 | 17 18 +12V analog | 19 20 Left Audio GND | 21 22 -12V (Audio) | 23 24 Right Audio \ 25 26 !Reset (active low) !Reset is Active Low. MIDI In/Out and !Reset are TTL level signals. MIDI is transmitted at 31250 Baud, 8 bits, 1 start bit, 1 stop bit. Some more technical data: The power consumption of the YAMAHA DB50XG board is about 2 Watts. So this makes about 400mA that are needed at the +5V pin. Consider this when taking power from anywhere. The +12V and -12V are only used for the audio amplifier on the sound card. So they do not require a lot of power. The YAMAHA DB50XG sound card does not send any usable information on its MIDI Out pin. At least I did not find any information in the user manual that indicate that the sound card is capable of sending any MIDI data. So we will not connect the MIDI out pin of the sound card. This saves us some work and it allows us to share the serial port between any external devices and the sound card. It is very important that the sound card gets a reset impulse after the power has been switched on. Without giving a reset, the card won't react and stay quiet. Before I knew that there is a reset pin I was fiddling around for three days searching for an error in my adaptor. ;-( The Amiga RS232 serial port uses +12V and -12V for sending the signals. As we don't want to burn our sound card, we will have to convert this to TTL signal level (+5V / 0V) before feeding it to the card. Two chips I know about are capable of doing this: The MAX 232 from MAXIM - it is a bi-directional and dual RS232<->TTL converter. The MC1489 chip from Motorola (or the compatible SN75189 chip) is a quadruple RS232 receiver that only converts from RS232 to TTL. The MAX232 is more expensive than the MC1489 and requires a more complicated circuitry. It uses four capacitors (22yF) for creating -5V, +10V and -10V from a single +5V VCC current. As it is bi-directional, you can feed the sound card's MIDI out signal into the serial port of the Amiga. But in this case you may _NOT_ connect any external device to the serial port at the same time. Imagine the modem and the MAX232 chip trying to send data to the RxD pin at the same time. That will probably destroy either the modem's or the MAX232's output drivers. And by the way, you can also grab the Amiga's TxD Data directly from the Paula chip, right before it is converted to RS232 level. The data signal is present at pin 40 of Paula. But be careful. It can be very easy to damage your Paula chip. I recommend using the serial port and a converter chip. The !Reset pin can be connected to +5V through a 4.7kOhm pull up resistor. Use a switch or a button for connecting this pin to GND. When you activate the switch or button, the sound card will execute an internal reset because pin 26 goes to 0V. The reset must be given after you turn on the computer or the sound card will refuse to work. You may optionally add an automated reset logic (e.g. by replacing the switch by an adequately dimensioned capacitor). You can also use the Amiga's internal system reset signal. This is how the reset switch should be connected. The resistor is used as a so called "pull up" resistor here. ---------- +5V ---| 4.7 kOhm |-----x---- to pin 26 (!Reset) ---------- | | \ switch closed means card is in reset state \ (turned off and silent) | | to GND I recommend using a switch for manually resetting the sound card. This works as an "emergency" switch in case something on the MIDI bus went wrong and the sound card produces a persistent, awful and loud sound. You can also turn off the sound card by giving it a constant reset signal. Never connect a headphone directly to the sound card's audio out! You will probably kill the sound card's internal amplifier. Always connect an amplifier (e.g. HIFI set) to the output of the sound card. If you want to mix the sound card's audio signal with that of your Amiga, you can use either an external mixing console or you can build a small electronic stereo mixer using two Op-Amps. Never try to mix the audio by directly connecting the sound card's audio-out directly to the Amiga's audio-out! An internal sound card comes in handy. I am using a Toccata card for mixing the audio signals. The pinout of the converter chips --------------------------------- Here comes the pinout of the MAXIM MAX232 chip. ___ ___ These pins / O| \/ |O +VCC = 5 Volts have to be | O| |O GND conncted to | O| |O RS232 Out (C) 22yF | O| MAX232 |O RS232 In (D) capacitors | O| |O TTL Out (D) (see below) \ O| |O TTL In (C) RS232 Out (B) O| |O TTL In (B) RS232 In (A) O|________|O TTL Out (A) ----- 1 This is how the capacitors | have to be connected to pins 22yF | 1-6 of the MAX 232 chip. | |+ | They are needed for creating ----| |--------|------ 2 internal voltages of +10V, | | | +| -10V and -5V from of the +VCC === 22yF----- (GND) ----- Use electrolyte capacitors and | mind the polarity (given by the ----- 3 + signs). You don't want the capacitors explode right in your computer, don't you? ----- 4 +| 22yF----- ----- | ----- 5 22yF +| | ----| |--------------- 6 | | | === (GND) Here comes the pinout of the Motorola MC1489 chip. ___ ___ 1A O| \/ |O +VCC = 5 Volts Control 1 O| |O 4A 1Y O| MC1489 |O Control 4 2A O| or |O 4Y Control 2 O| SN75189|O 3A 2Y O| |O Control 3 GND O|________|O 3Y The A pins are the RS232 signal inputs, the Y pin is the TTL signal output. The Control pins specify the hysteresis. For our purpose, they should be left unconnected. The Internal version (A2000/A3000/A4000) ---------------------------------------- In the recent days, I have built a PC YAMAHA DB50XG sound card right into my Amiga 2000. I mounted the sound card to one of the metal "pads" that are covering the back side of the Zorro slots. So the sound card is now perfecly fitting into my Amiga. The adaptor for the serial port is a little board that resides on the internal serial port connector. This connector only exists in the Amiga 2000. It is located on the motherboard near the external connector of the serial port. So building an internal version for any Amigas other than the A2000 is somewhat more tricky, but possible of course. This is the pinout of the internal A2000 serial port connector. Unfortunately most internal A2000 turbo boards for the MMU slot reside directly above the connector and make it more difficult to access it. WARNING: The pinout given below is NOT the pinout of the serial port on the back side of your Amiga (which can be found in the addendum of your Amiga manual. The pinout below is an internal connector on the A2000 mother board only. Someone actually messed that up and wondered why it didn't work. GND 1 2 -5V TxD 3 4 Audio Out (left channel only) RxD 5 6 Audio In (to right channel only) RTS 7 8 E CTS 9 10 *INT2 DSR 11 12 LEDPOWER DGND 13 14 DTR CD 15 16 +5V 17 18 RI 20 +12V 21 22 *C2 23 24 *BAST 25 26 The only pin that is of interest for us, is the TxD pin for grabbing the MIDI data. The +5V line is *too weak* for giving the necessary power. Trust me, I tried it and the computer began crash over and over. The +12V pin at this connector (+12V User) is indirectly connected to system power with a 1N4001 diode which eats up approx 1.2 Volts. So you cannot get the full 12Volts at this pin. Conclusion: Get the power (+5V, GND, +12V) from a floppy or hard disk power connector. And where can you grab the -12 Volts from? I was soldering an additional pin into the connector, right at the non-existing pin 19. Then I connected this pin to -12V (not -12V User, as this lacks approximately 1.2V because of another diode). This required me to take the motherboard out of the computer. I am sure you can find a simpler solution. Have a look at the circuitry of your computer to find out where you can grab the -12 Volts. You can of course go directly to the main power connector on the motherboard. My adaptor board resides on the internal serial connector. Three cables are leading away from this adaptor board. One is a 3 wire power cable that leads to a floppy drive power connector. Another cable is a 6 wire cable that leads to the sound card itself. It carries power, MIDI data and Reset. I was using an old Joystick cable for this purpose. The last cable leads to a switch that I inserted into the front casing of the Amiga right next to the power LEDs. It is the reset (or ON/OFF) switch for the sound card. If you have an A3000 or A4000, you should grab the TxD pin from the back side of the serial port connector (so that you can still connect serial devices at the back side of your computer). Just solder a wire to the correct pin or use a clip for fixing the wire. For the sound card itself, I am using a 26 pin dual row male connector. This one has a 90 degree angle so that the wires lead away to the side of the sound card. This makes the whole construction somewhat more flat. For leading the Audio signal away from the sound card, you should use a shielded cable. Hint: Just cut a standard Chinch audio cable in two halves and solder the ends and the shielding to the appropriate pins of the connector. Be sure to connect the analog (audio) ground to the shielding of the audio cable. In most cases the left audio wire will be white, the right one red. As I own a toccata board, I bought a very cheap walkman headphone and cut off the wire. This fits perfectly into the internal AUX2 input of my toccata board. The external version (any Amiga) -------------------------------- Similar to the internal version described above, but - take the power (+5V, +12V, GND) externally from the floppy port. - take TxD and -12V externally from the serial port. Use standard Sub-D connectors with plastic or metallic casing. Be careful: A metallic or metallized casing does not insulate and may cause short circuits if you do not take care of that. The converter electronics may fit into the casing of the serial port SUB-D connector if you just use the MC1489 chip. Take care of the insulation. It may be wise to fill the whole interior of the SUB-D casing with hot plastic glue using a hot plastic glue gun. Or use wax from a candle. This should work as well. You may want to put the sound card into a box or a casing as well. This looks smarter and prevents damage to the sound card. Take care that no connector ever touches any metallic surface. This can cause a short circuit and damage the sound card and/or your computer or the power supply. Same thing for the sound card. Never put it on a metallic surface. Always put some insulation (e.g. sheet of paper) in between. For creating an adaptor that does not allocate the serial port and/or floppy port, you can use two-sided Sub-D casings. Put a male connector on one side and a female connector to the other side. Connect all the 25 or 23 pins internally with a flat ribbon cable. And of course connect the converter electronics and/or the power cable to the correct pins. And pray that all this fits into the casing. Never connect or disconnect the floppy and serial connectors of your adapter when the computer is running. Turn off the computer before. After restarting, do not forget to reset the sound card after turning on the computer or you will not hear anything. Recommended Software -------------------- - MIDIPlay 2.65b by Janne Syväniemi (Shareware, available on AmiNet) - Bars & Pipes by Blue Ribbon Soundworks (available for FREE through CompuServe). A professional MIDI sequencer with Drag & Drop and some very innovative features. - SuperJam by Blue Ribbon Soundworks (also available for FREE through CompuServe). A kind of an automated accompaniment sequencer with several different styles. General MIDI support only. - MIDITracker (available on AmiNet). Kind of a SoundTracker for MIDI. No external MIDI keyboard required for composing. - DeluxeMusic 2.0 by Electronic Arts for composing on a note sheet. General MIDI support only. - Camouflage (demo available on Aminet), a MIDI sequencer - Dominator (demo available on Aminet), a MIDI sequencer - OctaMED 6.0 (demo available on Aminet), a tracker capable of doing MIDI as well. - GMPlay 1.2 (available on Aminet) a General MIDI player that does not require a sound card or any external devices. Written by Alessandro de Luca and _me_. - The XPK compression package and xpkSHRI Library (available on Aminet). SHRI gives an excellent compression ratio when used at 100% efficiency on MIDI files. The files are often shrinked to 20% of their original length. Make sure to decompress the files before loading them into any MIDI software! This list is incomplete. Any suggestions welcome. Recommended Websites and Songs ------------------------------ Have a look at www.yamaha.com or the local YAMAHA web server in your country. They offer (PC) software and MIDI files as well as technical data and valuable tips. There are a lot of internet sites that offer song collections for the Yamaha DB50XG. The best site is probably "The XG Home" at "http://www.ids.net/~marshall/xg.htm" The link "The Songs" at the bottom of the page will take you to the collection of midi files. Links to the composers' pages are also provided. The songs on this server are especially written for the Yamaha DB50XG sound card and may sound very different on other MIDI equipment. There are more web sites that offer XG midi files. Another excellent German site was created by Michael Banz. His site offers more than 500 XG midi files (even more that can be found on Marshall's XG Home page). Be sure to check out this URL: "http://www.castrop-rauxel.netsurf.de/~michael.banz/" A lot of cover version of original chart hits and old C-64 songs in XG MIDI format can be found on "http://www.cs.vu.nl/~arthur/xg.html" Be sure to get the song "Children.MID". It is amazing, although it starts quite dull (just as the original song from the charts). Other recommended songs: Running Scared.MID - acid-trance, really exciting Marin County Morning.MID - ballad, ressembles to Fleetwood Mac Children.MID - charts-hit: Robert Miles, "Children", very good Locust Dance.MID - unusual rhythms and a very good E-guitar solo It's Only Me.MID - sentimental song with good sound Images.MID - house-trance, spacy, excellent! Suburbia.MID - jungle-trance, quite good Mr. Bones.MID - true blues-rock, hammond-organ and E-guitar Sea Scape.MID - moody song with undersea sounds, wales, relaxing Heart Land.MID - melodic song, lot of organ Hypnotica.MID - melodic song, partly trance-like, excellent Espagnol.MID - perfect (!!!) Flamenco, excellent Interleaver.MID - perfect trance, cool organs Memories Of Arden Road.MID - rock-ballad, cool E-guitar solos Jock Rock.MID - rock music, like some kind of TV title song D-Shake.MID - spacy acid sequence, lots of filter and echo X-Cita.MID - spacy trance Feel The Energy.MID - spacy song, ressembles to Robert Miles "Children" Over The Rainbow.MID - well-known piece from a musical, lots of violins Tek Toys.MID - trance or breakbeat, nice spacy sound Sonic Surfing Part 3.MID - trance with cool synth bass Water Flowing Uphill.MID - wonderful ballad Secret Garden.MID - wonderful dreamy song, very cool sfx Quest For Lost Heroes.MID - hard rock, excellent guitars, live atmosphere This list is incomplete and reflects my personal taste. Meanwhile lots of excellent new XG midi files have been released. If you intend to connect different sound cards, just let me know what web sites you can recommend. LEGAL STUFF ----------- Any commercial use of this text is explicitly forbidden without my permission. This text may only be spread through computer networks (newsgroups, AmiNet) if it is left unchanged. There is no warranty for correctness of the above information. Building the interface is at your own risk. I cannot be made liable for any hardware damage to your sound card and/or your Amiga. SoundBlaster and WaveBlaster are trademarks of Creative Labs Inc. Please excuse any misspellings or the choice of inadequate technical terms. I may be an expert in the German language, but in English, I am definitely not. Contact me ---------- Suggestions, corrections and improvements welcome. Drop me an EMail if you succeeded in building the interface. I am currently writing some software for accessing all the sound card's instruments. EMail to: flowerp@eikon.e-technik.tu-muenchen.de Please retry if the EMail server is down. (c) 1996,97 Christian Buchner // \X/ Flowerpower