herbie@bruce.cs.monash.OZ.AU (Andrew Herbert) (10/22/90)
Following is information regarding midi cards for IBM PCs. As well as the cards mentioned (Music Quest MQX-16S, Roland MPU-IPC), Voyetra also make midi cards (v-22, v-24 and variations) as discussed in a recent news release. Andrew ------------------------------------------------------------ From: mike@relgyro.Stanford.EDU (Mike Macgirvin) I use a Music Quest card with Chase Lock. I forget the exact model nomenclature, but it is the '16' (MQ-16 or something like that). > Is programming information available? Music Quest sells a book and some sample programs for about $40 U.S. > What software is available for the card? > What (other cards) is the card compatible with? The card is 'MPU-401' compatible (the going standard) so most MIDI software will work with it. I have had no compatibility problems. > What are the special or distinguishing features? > (e.g. n byte transmit/receive buffers) I don't know the buffer sizes. This card is distinguished by 'chase- lock synchronization'. This allows me to use my software sequencer as a multi-track recorder, synchronized with an analog 8-track recorder, giving me (virtually) 19 mixeable tracks (This is dependant on the actual MIDI hardware involved; your mileage may vary). 4 channels - drum machine 8 channels - synthesizer (multi mode) 7 channels - analog 1 channel - wasted analog click track to sync things There are other 'sync' cards. This one allows you to start the tape recorder anywhere (not just the beginning) and the MIDI sequencer will start up at the right place. > What is the approximate cost? $200 U.S. A basic card without sync costs about $100 U.S. A low cost sync card (the tape has to start from the beginning each time) is available for $150 U.S. >Also, a general question: are these cards necessarily interrupt-driven? >I have a terrible feeling I don't have any spare interrupt lines (com1, >inport mouse, 8514/A clone). Most all cards are interrupt driven. You may be lucky on the AT, however, since it contains a few extra interrupts that aren't available on a PC. Even with a PC, you can sometimes get away with sharing an interrupt with the COM port, since most people don't use the modem at the same time they are writing songs... ------------------------------------------------------------ From: 6600bori%ucsbuxa@hub.ucsb.edu (Boris Burtin) I recently bought an MQX-16S, manufactured by Music Quest, and am extremely happy with it. Just with the software supplied, and a simple MIDIEX send/ receive program, I was able to load and save patches from my ESQ-1 and do real-time chase-lock syncing to tape - both audio and video - that means that as the tape plays, anywhere, the computer reads the sync track and drives the sequencer to play at that same spot, using song position pointer. The card only ran me $199. Music Quest offers two programming packages with routines for all the major languages for $39.95 each. The card is configurable to run on several interrupts, but the default for all standard MIDI cards is int2. Hope that helps! [and in a later letter] I have not yet ordered the programming supplements, so I couldn't answer your question about that. I do know that you need some assembly language routines to access the MIDI card - those I don't understand - I just use some routines a friend of mine gave me. As far as the included software, you are able to: - use it as a simple, 1-track sequencer - interpret MIDI info, or display it in hex - stripe SMPTE or song position pointer info on tape - read SMPTE or SPP from tape and sync an EXTERNAL sequencer to tape those are the major features. As far as I understand, Cakewalk Pro, among other software, supports the MQX cards specifically, allowing you to use SMPTE. ------------------------------------------------------------ From: krisku@ironman.hut.fi Hi! You wanted to know some things about Midi interfaces for the PC. Let me shortly tell you about what I have... ROLAND MPU-IPC -------------- This is the official Midi interface for the PC, XT and AT. It is fully compatible with the MPU-401 (in fact the MPU-IPC is a MPU-401 with PC interface). MPU stands for Midi Processing Unit. It is pretty hard for me to say how much it costs because Finland is pretty expensive, but I should guess something around $150-200. Most software is made for use with the MPU-401 or compatibles (I have heard about some MQX), so if you have a MPU-401 you can use every kind of software unless it is stated that a you MUST have a special card (like AdLib, Soundblaster, CM32L or other similar products). When I bought my MPU-IPC I only got with it a few sheets of paper, including some hardware specifications and a circuit diagram. I contacted the Finnish Roland-center and from there I got a technical reference manual, which was about 100 pages thick and included instructions on how to program the card and several programming examples. Hardware: the MPU-IPC consists of two pieces connected to each other with a cable; the interface-card to put into the computer and the actual MPU-unit where all connectors are. The MPU-unit is 165*50*31 mm in size and contains the following connectors: 1 MIDI IN 2 MIDI OUT (identical) 1 TAPE IN (FSK SYNC) 1 TAPE OUT (FSK SYNC) 1 METRONOME OUT (if you find the built-in speaker to weak) 1 MIDI SYNC (some MPU-IPCs don't have it!) The MPU-IPC uses I/O ports 0330h, 0331h and IRQ2, but they can all be changed with jumpers on the interface card. Most programs allow you to change the addresses and IRQs used by the program also. Features of the MPU-401: a) an intelligent interface allowing the HOST (computer) to perform other tasks while the MPU-401 is recording and/or playing. The MPU-401 operates as a 'background' processor using interrupts to request data to and/or from the host. b) because of the above, disk I/O, screen updates, and all kinds of other tasks can be performed while recording or playing MIDI data. c) the MPU-401 functions as an 8 track MIDI data recorder, taking care of all aspects of recording and playing. Each track can be polyphonical and multichanneled. By using interrupts the MPU-401 requests data for every channel and also signals if there is some incoming data to be read from the port. d) The MPU-401 internally takes care of TEMPO, BEATS PER MEASURE, METRONOME (with or without accents or quiet), RELATIVE TEMPO, internal or external syncronization (miditiming clocks, Roland DIN sync or FSK sync). In addition the internal TIMEBASE can be set to one of seven different divisions per beat; 48, 72, 96, 120, 144, 168 or 192. e) the most commonly used functions are enabled at power up as defaults, but these values may be changed on the fly by the computer. The computer can become the conductor of the MPU-401 and so change the tempo gradually or immediately in real time. f) the MPU-401 contains 1 RECORD COUNTER, 8 PLAY COUNTERS and 1 CONDUCTOR TIMER for timing special data, a MIDI IN TABLE which flags each incoming midi note on and clears it upon receiving note off or all notes off, 4 CHANNEL REFERENCE TABLES working like the midi in table but on outgoing notes. 8 PLAY BUFFERS which hold the next MIDI data to be sent for each internal track. A PROGRAM CHANGE BUFFER which holds the last midi program change since the most recent stop. A MIDI CHANNEL FILTER to allow only selected MIDI channels to pass, and a MIDI MESSAGE FILTER for screening out selected MIDI controllers. A programmable AUDIO METRONOME which will play any time signature with or without accents. etc, etc... g) for simpler applications the MPU-401 also features a UART mode which turn off all intelligent commands in the interface and after that the interface can simply be used for receiving or sending raw MIDI data. h) and much more... As a conclusion it can be said that the MPU-401 is a very powerful interface and it doesn't require too much to make a simple sequencer program as the interface can take care of all timing and processing. The computer need only to manage memory and make sure that the MPU-401 gets all the the data it requires. Many new games (especially from Sierra) nowadays include music for several popular sound systems. If for example the MT-32 is listed in the game (the MT-32 is a pretty cheap multitimbral synthesizer), then it's assumed that you have a MPU-401 compatible MIDI interface in your computer so the game can access the synth. I now realize that this became a rather long text, but I hope you get something out of it. If you want to know more about the feel very free to contact me about it... With friendly greetings... Kai Risku - krisku@niksula.hut.fi ------------------------------------------------------------ End of summary.