


          HOW TO USE THE AUDIOTRIX PRO MPU-401 INTERFACE


          ==============================================





- Introduction


- Connecting the Audiotrix Pro to your external MIDI device


- Choosing an I/O port and an IRQ for the MPU-401 interface 


  (Configuring SETUPPRO.EXE)


- Using SETMPU.EXE


- Configuring the Audiotrix Pro for a DOS-based sequencing 


  environment


- Configuring the Audiotrix Pro for a Windows-based sequencing 


  environment


- Configuring the Audiotrix Pro for a DOS-based gaming environment


- Frequently Asked Questions


- How to reach Mediatrix technical support











============


Introduction


============


The MPU-401 interface of the Audiotrix Pro is key to the


Audiotrix Pro's excellent DOS game compatibility and to its 


ability to easily interface with external MIDI instruments.  


Whereas many other sound boards require you to install a 


proprietary Windows driver to enable the sound card MIDI input 


and output, the Audiotrix Pro's MPU-401 interface behaves exactly 


like a Roland MPU-IPC adapter (although only able to act in the 


non-intelligent mode).





The following text explains in detail how to configure the Audiotrix


Pro MPU-401 interface for both DOS-based and Windows-based sequencing


environments.  Further on, it explains how the MPU-401 interface 


can be used under DOS games offering General MIDI music.








=========================================================


Connecting the Audiotrix Pro to your external MIDI device


=========================================================


On the back of the Audiotrix Pro you will find a DB-15 connector


which normally acts as a Joystick Port.  Attaching the supplied 


Audiotrix Pro MIDI/Joystick cable to the DB-15 port will provide 


your system with a MIDI in and a MIDI out which can be used to 


connect external MIDI devices to your computer.





The steps for connecting the Audiotrix Pro to your external MIDI 


device using the Audiotrix Pro MIDI/Joystick cable are the following:





1.  Make sure that the joystick-type selector jumpers on the 


Audiotrix Pro are set to the "single joystick/MIDI" option, as shown 


on page 14 of the Audiotrix Pro User's Manual.  Please note that if 


you bought the Audiotrix Pro with the MIDI cable included in the 


box, the jumpers should already be in the "single joystick/MIDI" 


setting.





2.  If you have a joystick attached to the Audiotrix Pro MIDI/


Joystick port, please temporarily remove it and attach the Audiotrix 


Pro MIDI/Joystick cable.





3.  Connect the Audiotrix Pro MIDI/Joystick cable wire labeled as 


"OUT" to the "IN" jack of your  MIDI device.





4.  Connect the Audiotrix Pro MIDI/Joystick cable wire labeled as 


"IN" to the "OUT" jack of your MIDI device.





5.  Re-connect your joystick to the Audiotrix Pro MIDI/Joystick 


cable DB-15 connector.





Now you are ready to configure the Audiotrix Pro MPU-401.











=========================================================


Choosing an I/O port and an IRQ for the MPU-401 interface


=========================================================


To use an external MIDI device, you must first configure the


Audiotrix Pro MPU-401 interface within DOS.  To perform the 


configuration, run the SETUPPRO.EXE Audiotrix Pro configuration 


program from the \TRXPRO directory.





Once in SETUPPRO, use the Tab key to change fields until you reach 


the MPU-401 Interrupt field.  You must then select an interrupt 


which will be used to process the messages to/from the external 


MIDI device.  Usually, interrupts are only needed when recording 


MIDI events or when using the Windows MPU-401 driver.  MIDI playback 


through the MPU-401 MIDI interface (playing games) does not need to 


be interrupt driven, but DOS-based MIDI recording requires an 


interrupt.  Usually IRQ 5 is the best IRQ to devote to MPU-401 


recording and playback, however, IRQ 9 is also known to be very 


good.  Keep in mind that in this situation, 16-bit digital audio 


wave playback should be moved to IRQ10 or 11, because IRQ7 is 


usually devoted to the Sound Blaster interface.





You must also select the address of the MPU-401 interface.  The 


default address of 330 is the only address which is common between 


SETUPPRO and the Windows "Roland MPU-401" driver (I/O port 330 is 


widely recognized as the established standard I/O port of the 


Roland MPU-401 and all other MPU-401 compatible MIDI interfaces).  


Some SCSI adapters (i.e. Adaptec 1542) are factory defaulted to 


I/O 330, which conflicts with the MPU-401 MIDI port.  If you have 


a conflict and you want to use the MPU-401, change the address of 


your SCSI adapter.





Once you finish configuring the MPU-401 settings, press <Enter> 


and save the settings as the default startup settings.











================


Using SETMPU.EXE


================


The ability to disconnect the OPL4 General MIDI synthesizer found


on the Audiotrix Pro from its onboard MPU-401 MIDI interface is 


one of the most important feature which sets the Audiotrix Pro 


apart from other MPU-401 compatible soundcards.





Think of the Audiotrix Pro as a "Virtual MIDI jack".  The SETMPU.EXE 


utility controls the state of the Audiotrix Pro MPU-401 OPL4 MIDI 


Interpretation process.  A brief explanation and understanding of 


the behavior of the MPU-401 side of the Audiotrix Pro is necessary 


to appreciate the benifits related to the flexibility of the 


Audiotrix Pro's MPU-401 interface.





The status of the MPU-401 interface of the Audiotrix Pro can be 


viewed by running the SETMPU.EXE DOS utility from the \TRXPRO 


sub-directory without any command line parameters.  After doing 


so, you should get a display which looks like the following:





Audiotrix Pro MPU-401 Setup, V 1.XX


Copyright (C) 1994, Mediatrix Inc. All Rights Reserved.





MPU-401 Interface V 1.XX





USE: SETMPU /T<flag> /M<switches>


          /T[0|1] = MPU-401 Mode Select,


              * 0 = General MIDI Mode


                1 = MT-32 Mode


         /M[0123] = MPU-401 Switch State,


                0 = MIDI-In     --> OPL4


              * 1 = MIDI-In     --> MPU-401 In


                2 = MPU-401 Out --> MIDI Out


              * 3 = MPU-401 Out --> OPL4





An asterix next to numbers 0,1,2,3 on this picture represent the 


SETMPU flags and switches which are active.








The following is a description of the command line parameters to 


the SETMPU.EXE DOS utility:





/T[0|1] = MPU-401 Mode Select





This parameter is used to select the mode in which the MPU-401 


will play. You can use only one setting or the other.


     


     0 = General MIDI Mode  





This is the default state of the MPU-401 interface.  In this 


condition, the MPU-401 will play using the standard General MIDI 


instrument patch map.





     1 = MT-32 Mode





This option sets the MPU-401 to use the Roland MT-32 instrument 


patch map.  This mode is currently in development and will be 


available soon.





Example: SETMPU /T1 = Use MT-32 Mode





/M[0123] = MPU-401 Switch State


This parameter allows you to select the MIDI-IN and the MPU-401 


OUT for MIDI devices.  When using this parameter, you may specify 


any or all of the choices available.       





        0 = MIDI-In	--> OPL4


      * 1 = MIDI-In	--> MPU-401 In   (Default MIDI-IN)


        2 = MPU-401 Out	--> MIDI Out


      * 3 = MPU-401 Out	--> OPL4   (Default MPU-401 OUT)





Examples: 


     SETMPU /M13  


	MIDI-In 	= MPU-401 In


	MPU-401 Out	= OPL4


     SETMPU /M0123 


	MIDI-In 	= OPL4 & MPU-401 In


	MPU-401 Out	= MIDI Out & OPL4





The following is a more in-depth description of the behavior of 


the SETMPU switches:





0 = MIDI-In  --> OPL4:  This option allows you to direct all input 


from an external MIDI device to the OPL4.  If this option is set, 


an external device sending commands to the MIDI In jack on the 


Audiotrix Pro will make the OPL4 produce the appropriate sound.  


Using this option by itself (ie: SETMPU /M0) is particularly useful 


if you have another MPU-401 interface in your computer and want 


to be able to use the OPL4 from an external MIDI device but do 


not want commands to be echoed to the MIDI-IN port.





1 = MIDI-In  --> MPU-401 In:  This option allows you to receive 


input from an external MIDI device.  By enabling this option, a 


software application will be able to capture the data coming 


through the PC MPU-401 MIDI port and save it.  If this option 


is not set, however, you will not be able to record any command 


received on the MIDI In connector with the computer.





2 = MPU-401 Out  --> MIDI Out:  This option allows commands sent 


to the Audiotrix Pro MPU-401 interface to be sent to an external 


MIDI device.  This option, if in use with option 1, (i.e., option 


0 and 3 not enabled) will make the Audiotrix Pro act as a plain 


MPU-401 interface.  This setup is very useful with Windows sequencers 


when you want the sequencer to let the Windows driver talk to the 


OPL4, and keep the use of the Roland MPU-401 driver for other 


external MIDI devices.





3 = MPU-401 Out  --> OPL4:  This option allows commands sent to 


the Audiotrix Pro MPU-401 interface to be sent to the OPL4, 


therefore making the OPL4 produce a sound.  Unless this option 


is set, MPU-401-based MIDI playback will not make the OPL4 produce 


a sound.  This option is useful when you want to send data to 


external MIDI devices without having the OPL4 respond to the data.   


This option is absolutely necessary for DOS games if you want the 


Audiotrix Pro to emit sounds when the software is configured for 


General MIDI). If this option is not enabled, the OPL4 synthesizer 


will only produce sounds if the software is talking directly to it 


(the DOS JukePro, PlayMIDI and the OPL4 Windows Driver are typical 


examples).





WARNING:  The OPL4 synthesizer of the Audiotrix Pro will accept 


MPU-401 commands and direct commands at the same time.  This 


situation should be avoided since the results can be unpredictable 


(like completely distorted sound).  Example:  When using any 


sequencer with the Roland MPU-401 Windows Driver selected as 


the output device,  make sure that NO commands sent to the MPU-401 


interface are echoed to the OPL4 by setting the MPU-401 interface 


with options 1 and 2 only (/M12 switch).











====================================================================


Configuring the Audiotrix Pro for a DOS-based sequencing environment


====================================================================





------------------------------


Command to use:  SETMPU /M0123


------------------------------





The Audiotrix Pro is one of the few sound cards supporting a 


DOS-based sequencing environment. Under such a restrained 


environment, with the Audiotrix Pro, you are limited to MPU-401 


playback of General MIDI.  Under Windows, you are able to select 


the MPU-401 as the output device, along with any of the Multimedia 


MIDI Windows Drivers, such as the Audiotrix Pro Direct OPL4 Windows 


Driver.  This frees up the MPU-401 to allow output to external MIDI 


devices without the OPL4 playing a sound.





Usually, in a DOS sequencing environment, what you want to do is 


to have the Audiotrix OPL4 synthesizer respond to the MPU-401 


commands sent out by your sequencing software.  You also want to 


have the Audiotrix Pro OPL4 Synthesizer play music when responding 


to incoming MIDI data coming from MPU-401-IN port.





To configure the Audiotrix Pro MPU-401 interface using the SETMPU.EXE 


utility (supplied with the Audiotrix Pro setup disk)





1. Make sure there is no incoming MIDI data being fed to the 


Audiotrix Pro MPU-401 interface (SETMPU cannot configure the MPU-401 


interface when the MPU-401 interface receives data)  To be certain, 


shut off whatever external MIDI unit connected to the Audiotrix Pro.  





Notice:  Many keyboards continually send Status Check or "Presence" 


data bytes, so keep the MIDI unit turned off while running SETMPU.EXE)





2. Run SETMPU.EXE with the /M0123 command so that all MPU-401 


switches are active.  This is the recommended setting for a DOS-based 


sequencing environment.








========================================================================


Configuring the Audiotrix Pro for a Windows-based sequencing environment


========================================================================





----------------------------


Command to use:  SETMPU /M12


----------------------------





The Audiotrix Pro is ideally suited for a Windows-based sequencing 


environment.  Because the Audiotrix Pro MIDI port is compatible 


with the Roland MPU-401 adapter, it can be used seamlessly to 


access an external MIDI.  In a dual configuration of the Audiotrix 


Pro Windows OPL4 MIDI Synthesizer driver and Roland MPU-401, up to 


16 other extra MIDI channels are available to communicate with 


external MIDI devices.  With more recent sequencers, it is not 


necessary to create a MIDI mapper environemnt, as the sequencing 


software will do this for you.  In fact, configuring the Audiotrix 


Pro in a Windows sequencing environment can be done in two different 


manners, through the standard Microsoft Windows MIDI mapper  or 


through the internal mapper of the sequencing environment.





To configure the Audiotrix Pro for a Windows-based sequencing 


environment





1. Make sure there is no incoming MIDI data being fed to the 


Audiotrix Pro MPU-401 interface.  (SETMPU cannot configure the 


MPU-401 interface when the MPU-401 interface receives data.)  


To be certain, shut off whatever external MIDI unit connected 


to the Audiotrix  Pro.  Notice: many keyboards continually send 


Status Check or "Presence" data bytes, so keep the MIDI unit turned 


off while running SETMPU.EXE)





2. Before starting Windows, run the SETMPU.EXE utility with switches 


/M12 (this makes the Audiotrix Pro MPU-401 interface behave as if 


it was not connected to the OPL4 synthesizer). This is the 


recommended setting for a Windows-based sequencing environment.  


Unless you establish some kind of a connection between the sequencer 


software and the OPL4 Windows driver, no wavetable sound will come 


out of the Audiotrix Pro.  Using switches /M12 assures you that you 


will not end up in a situation where both the Audiotrix Pro OPL4 


MIDI synthesizer and the external MIDI unit play the same data 


concurrently.  You might also want to put the SETMPU.EXE command 


in your AUTOEXEC.BAT.  The only warning is that before playing any 


game, you will need to set the MPU-401 interface to mode /M3 in 


order to have OPL4-based MPU-401 MIDI playback.  





3. After starting Windows, check to see if the Windows Roland 


MPU-401 MIDI driver is loaded the Control Panel.  If the "Roland 


MPU-401" is already listed, see below.  If it is not shown, select 


"Add".  A list of available drivers will appear and you will have 


a choice called "Roland MPU-401".  Select this choice and click 


on "OK" to install it.  You might need your original Windows 


diskettes to do this and if so, Windows will tell you which disk 


it requires.





You must then configure or setup the driver.  In the configuration 


screen for the "Roland MPU-401 driver", you must select the same 


values as you chose in SETUPPRO for the MPU-401 (Port 330, Interrupt 5).





4. Now you need to make a choice:  If you are using an old version 


of a Windows-based MIDI sequencer, for example applications that 


have no MIDI mapping functions like the Audiotrix Pro JukeBox, you 


will probably have to use the Windows MIDI Mapper.  Most recent 


sequencers (Cakewalk 3.0 and up, Cubase 2.5 and up) are good 


examples, however, they have their own internal MIDI mapper, you 


will probably not need to go this far.











================================================================


Configuring the Audiotrix Pro for a DOS-based gaming environment


================================================================





--------------------------


Command to use: SETMPU /M3


--------------------------





Under a DOS gaming environment, only switch 3 is necessary because 


here we are only considering playback of General MIDI music. 


(i.e.:, there is no need to consider capturing MIDI data with the 


computer).  In other words, what is desired is that whatever the 


game software wants to send to the MPU-401 MIDI port gets 


interpreted and played by the OPL4.   





1. Make sure there is no incoming MIDI data being fed to the 


Audiotrix Pro MPU-401 interface (SETMPU cannot configure the MPU-401 


interface when the MPU-401 interface receives data) To be certain, 


shut off wathever external MIDI unit connected to the Audiotrix  Pro.  





Notice: many keyboards continually send Status Check or "Presence" 


data bytes, so keep the MIDI unit turned off while running SETMPU.EXE)





2. Run SETMPU.EXE with the /M3 command.  This is the recommended 


setting for a DOS-based gaming environment)











==========================


Frequently asked questions


==========================


Here are a few problems you might encounter with SETMPU, or with the


Audiotrix Pro MPU-401 interface in general.





Q:  SETMPU gives me the following message: "Audiotrix Pro MPU-401 


    interface not responding"





A:  This message means that the MPU-401 interface is currently in 


    use by another application.  You will often see this message if 


    you are in a Windows sequencer, and you try to change the SETMPU 


    settings from a DOS Session.  To resolve this problem, get out 


    of the sequencer (or any program using the MPU-401 driver), and 


    try using SETMPU again.








Q:  SETMPU tells me switches "/M123" are enabled but I haven't 


    selected those options.





A:  This problem occurs because of real-time clock signals coming 


    from your synthesizer keyboard.  To resolve this problem, turn 


    off your synthesizer keyboard before using SETMPU, and turn it 


    back on after you finish.  Often, the best solution is to 


    initialize SETMPU with the settings you want from your 


    AUTOEXEC.BAT.  When you subsequently turn on your synthesizer


    keyboard after booting up, you should not even see this problem.








Q:  I have a MIDI cable that I used with my Sound Blaster card.  


    Will it work with the Audiotrix Pro?





A:  The Audiotrix Pro MIDI cable is not compatible with a "Sound 


    Blaster" MIDI cable.  The opto-isolator circuitry found on 


    "Sound Blaster" cables is not required with the Audiotrix Pro. 


    If you did not get a MIDI cable at the time of purchase, please 


    contact Mediatrix to purchase one or to obtain the proper pinout 


    schematic.








Q:  My Windows sequencer tells me I have no input device driver 


    installed.





A:  You have not installed the "Roland MPU-401" driver.  Please 


    refer to the section "Configuring the Audiotrix Pro for a 


    Windows-based sequencing environment".








Q:  When I play MIDI files, I want to use my external MIDI device 


    to play and record music.





A:  You must then use the SETMPU /M12 switch.








Q:  SETMPU.EXE does not want to remember the command line switches.





A:  When running SETMPU.EXE, make sure that no MIDI devices are 


    sending commands to the MPU-401 interface of the Audiotrix Pro 


    (turn off your synthesizer).  If this still does not solve the 


    problem, try slowing down your computer by turning off the 


    TURBO switch while running SETMPU.EXE (you can re-enable the 


    TURBO after).











========================================


How to reach Mediatrix Technical Support


========================================


Tel:                   (819) 829-8749 ext. 25


                       (9:00 a.m. - 5:00 p.m. EST)


Fax:                   (819) 829-5100


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Compuserve:            Go Mediatrix or GO MIDIDV then choose Mediatrix 


                       section or send messages to:  74774,1335


Internet:


   Technical Support:  techsupp@mediatrix.com


   FTP Server:         ftp://ftp.mediatrix.com in /pub/Mediatrix





