                Crystal Semiconductor Corporation

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





READ.ME - OS/2 Crystal Audio Device Driver Installation

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

This file contains information on how to install the Crystal Semiconductor

Corporation OS/2 Audio Device drivers.



In addition to Crystal Audio driver installation, this diskette includes

the IBM OPL3/FM MIDI synthesis device driver.



The following topics are covered in this READ.ME file:

1)  Installing on top of previous installations

2)  De-Installation of Sound Blaster Drivers

3)  System Requirements

4)  Files List for Crystal Audio Install Disk

5)  Crystal Audio for OS/2 Installation Procedure

6)  Device Driver Command Line Options

7)  Notes on Command Line Options

8)  Using Audio in DOS and Win-OS/2 Sessions

9)  Audio Concurrency Issues - OS/2, DOS, Win-OS/2

10) Plug and Play System Issues

11) Mixer Issues

12) DMA Buffer size and interrupt rates

13) MIDI Synthsis

14) MPU-401 - Wavetable installations

15) Web Site

16) Special notes on upgrading from driver version 1.xx to 2.xx.

17) Problems/Questions





1)  Installing on top of previous installations

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

This installation supports installation over all previous installations of

Crystal Audio device drivers as well as over-installation of IBM's

OPL-3 device driver.



No de-install is necessary prior to executing the OS/2 Multimedia

installation program, minstall.exe.



If you already have a non-Crystal device driver set installed,

it may be necessary to de-install those drivers before installing

Crystal Semiconductor audio device drivers.





2) De-Installation of Sound Blaster Drivers

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

With some Crystal Semiconductor parts, when installing OS/2 Merlin,

the system will incorrectly identify a Sound Blaster device - resulting

in erroneous installation of Creative Technologies Sound Blaster OS/2

device drivers.   This error occurs because most Crystal Semiconductor

CODECs include hardware support for Sound Blaster compatibility for DOS

game execution.



The Crystal Semiconductor installation (on this diskette) searches for

previous installations of Crystal Semiconductor drivers and

automatically de-installs them as part of the installation process.

It does not de-install Sound Blaster device drivers.



If your system presently has Sound Blaster OS/2 device drivers installed

and you do not have a Sound Blaster device installed, then you should

de-install the Sound Blaster OS/2 drivers prior to running this installation.



The de-installation of the Sound Blaster OS/2 device drivers requires

the following steps:



a) ERASE \MMOS2 and all subdirectories (this removes OS/2 multimedia support)

   Some files won't delete, this is okay.

b) Use OS/2 selective install to re-install OS/2 multimedia support.

   It will auto-detect the wrong device.  You should override

   the auto-detection to remove the Sound Blaster device driver.

   When correct, the installation panel will have no audio devices listed.

c) Complete selective installation and reboot

d) You are now prepared to use this diskette to install Crystal drivers.





3)  System Requirements

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



This installation and device drivers work on the following OS/2 systems:

    OS/2 Warp 3.0            ( Warp - Red box )

    OS/2 Warp 3.0 Fullpack   ( Warp - Blue box )

    OS/2 Warp Connect        ( Warp - Blue box )

    OS/2 Warp 4.0            ( Merlin )



In the above "Bluebox" and "Redbox" refer literally to the color of the

retail OS/2 box.



    Red box => "Warp for Windows".

               Uses previously installed Windows 3.1 binaries for WinOS2.



    Blue box => "Full pack".

               Windows 3.1 binaries are shipped with OS/2.





4)  File List for Crystal Audio Install Disk

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



List of all files (sorted by name)

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

    AMPMXMCD.DLL - IBM MMOS2 Amp Mixer update, installed Warp 3 if fixpack <26

    AMPMXMCD.F26 - IBM MMOS2 Amp Mixer update, installed Warp 3 if fixpack =26

    AUDIOIF.DLL  - IBM MMOS2 Audio VSD update, installed Warp 3 if fixpack <26

    AUDIOIF.F26  - IBM MMOS2 Audio VSD update, installed Warp 3 if fixpack =26

    CLOCK01.SYS  - IBM High res timer driver/clock, installed Warp 3 only

    CLOCK02.SYS  - IBM High res timer driver/clock, installed Warp 3 only

    CONTROL.SCR  - Installation control file

    CWBAUDI3.DRV - Crystal Windows 3.1 audio driver

    CWBAUDI3.INI - Crystal Windows 3.1 .INI file

    CWBFM.DRV    - Crystal Windows 3.1 FM driver

    CWADD.INI    - Crystal Windows 3.1 system.ini

    CWAUDIO.sys  - Crystal OS/2 Audio PDD/BASEDEV

    CARDINFO.DLL - Installation control resource DLL

    CWINST.DLL   - Crystal installation executable

    CWVAUDIO.SYS - Crystal OS/2 Audio VDD

    FILAUDFM.SCR - Installation control file, audio + FM installation

    FILAUDWT.SCR - Installation control file, audio + MPU-401 installation

    INSTALL.CMD  - Support double-click start of minstall.exe

    MIDIMAP.CFG  - Crystal Windows 3.1 FM MIDI map

    MIDIPLAY.ICO - Installation ICON for FM driver

    OPL3.SYS     - IBM OPL-3/FM OS/2 device driver

    OPL3RES.DLL  - Runtime capabilities for FM driver

    READ.ME      - This file

    TIMER0.SYS   - IBM High res timer driver/clock, installed on Warp only







Files listed by function:



Crystal OS/2 Audio driver

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

    CWAUDIO.SYS  - Crystal OS/2 Audio PDD

    CWVAUDIO.SYS - Crystal OS/2 Audio VDD



Crystal Windows 3.1 audio/fm driver

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

    CWBAUDI3.INI - Crystal Windows 3.1 .INI file     (installed on Merlin only)

    MIDIMAP.CFG  - Crystal Windows 3.1 FM MIDI map   (installed on Merlin only)

    CWBFM.DRV    - Crystal Windows 3.1 FM driver     (installed on Merlin only)

    CWBAUDI3.DRV - Crystal Windows 3.1 audio driver  (installed on Merlin only)

    CWADD.INI    - Crystal Windows 3.1 system.ini    (installed on Merlin only)



IBM OPL-3/FM OS/2 audio driver

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

    OPL3.SYS     - IBM OPL-3/FM OS/2 device driver

    OPL3RES.DLL  - Runtime capabilities for FM driver

    MIDIPLAY.ICO - Installation ICON for OPL-3 driver



Warp 3.0 OS Updates: (These are installed only on Warp 3.0 systems)

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

    AMPMXMCD.DLL - IBM MMOS2 Amp Mixer update        (installed Warp 3.0 only)

    AUDIOIF.DLL  - IBM MMOS2 Audio VSD update (Dart) (installed Warp 3.0 only)

    CLOCK01.SYS  - IBM High res timer driver/clock   (installed Warp 3.0 only)

    CLOCK02.SYS  - IBM High res timer driver/clock   (installed Warp 3.0 only)

    TIMER0.SYS   - IBM High res timer driver/clock   (installed Warp 3.0 only)



Installation files

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

    CONTROL.SCR  - Installation control file         (read by minstall.exe)

    CTRAUDFM SCR - Installation control file         (copied to control.scr)

    CTRAUDWT SCR   Installation control file         (copied to control.scr)

    FILAUDFM.SCR - Installation control file         (copy list for FM inst)

    FILAUDWT.SCR - Installation control file         (copy list for WT inst)

    CARDINFO.DLL - Installation resource DLL         (read by GenIn.dll)

    CWINST.DLL   - Crystal installation executable   (called by minstall.exe)

    READ.ME      - This file





5)  Crystal Audio for OS/2 Installation Procedure

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

To install device support, insert the Crystal Audio for OS/2 diskette in

drive A: (or whichever drive Crystal Audio for OS/2 diskette is in).

Start the Multimedia Application Install program which is located in the

Multimedia folder on the OS/2 desktop.

Alternatively, you can execute MINSTALL from an OS/2 command prompt.



Once you are in the multimedia installation program, select

Source Drive A: (or whichever drive Crystal Audio for OS/2 diskette is in).



The installation program will show

   Crystal Audio      (Pre-selected)

   IBM OPL-3 FM MIDI  (Pre-selected)



Click the install button to proceed with the installation.  Read and follow

the instructions provided by the installation program.



The following files are installed:



If system is Pre-Merlin  (Pre OS/2 Warp version 4 - Update CLOCK drivers)

   \OS2\BOOT\CLOCK01.SYS        IBM high resolution timer support

   \OS2\BOOT\CLOCK02.SYS        IBM high resolution timer support

   \OS2\BOOT\TIMER0.SYS         IBM high resolution timer support



If system is Pre-Merlin  (Pre OS/2 Warp version 4 and fixpack level < 26)

   \MMOS2\DLL\AMPMXMCD.DLL      IBM DLL for mixer API/DART (from DART DevCon)

   \MMOS2\DLL\AUDIOIF.DLL       IBM DLL for mixer API/DART (from DART DevCon)



If system is Pre-Merlin  (Pre OS/2 Warp version 4 and fixpack level is 26)

   \MMOS2\DLL\AMPMXMCD.F26      IBM standard FP 26 DLL (un-do prior installs)

   \MMOS2\DLL\AUDIOIF.F26       IBM standard FP 26 DLL (un-do prior installs)



If system is Pre-Merlin  (Pre OS/2 Warp version 4 and fixpack level > 26)

   No MMPM/2 system DLLs are updated



If IBM OPL3 is installed:

   \MMOS2\OPL3.SYS             IBM FM Driver

   \MMOS2\DLL\OPL3RES.DLL      IBM FM Driver runtime support DLL

   \MMOS2\INSTALL\MIDIPLAY.ICO Installation ICON



If Crystal Audio is installed:

   \OS2\BOOT\CWAUDIO.SYS        Crystal OS/2 Audio device driver

   \MMOS2\CWVAUDIO.sys          Crystal OS/2 Virtual Device Driver

   \MMOS2\DLL\CWINST.DLL        Crystal installation DLL



These lines lines will be added to the OS/2 CONFIG.SYS file.:

    BASEDEV=CWAUDIO.SYS /N:BSAUD1$ /X1:50 /X2:50 /LCAPT:X1X2

    DEVICE=C:\MMOS2\CWVAUDIO.SYS BSAUD1$



If OPL-3/FM is installed:

    BASEDEV=TIMER0.SYS

    DEVICE=C:\MMOS2\OPL3.SYS /P:388 /N:OPL31$





6)  Device Driver Command Line Options

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

The following tables describe the various command line options and setting

available for the Crystal Audio device drivers.



The options for setting IRQ/IO/DMA should be used only where

the default settings, BIOS assigned settings or operating system

assigned settings are not appropriate.



Run driver with "/V" to query how the codec was initialized.

See section "10" for more information.



CWAUDIO.SYS    -   OS/2 audio configuration device driver.



Option/Format  Description           Valid Values (* = Default Value)

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

/N:<name>      Name of PDD           BSAUD1$ (Supplied by install)

/V             Verbose Display

/X1:<percent>  AUX1 unmute/gain      0..100 (decimal) (*50) (usually "Line-In")

/X2:<percent>  AUX2 unmute/gain      0..100 (decimal) (*50) (usually CD-ROM)

/L:<percent>   LINE unmute/gain      0..100 (decimal) (*100)(FM volume)

/LCAPT:<input> Line-In record source X1, X2, *X1X2, L (X1X2 is mixed aux1+aux2)

/T:<value>     Inactivity power down 1..5 minutes     (*1)

/MBY:<0,1>     Mono bypass           *1 (mono-in connected to mono-out)

/MIM:<0,1>     Mono input mute       *1 (mono-in not connected to input mixer)

/MOM:<0,1>     Mono out mute         *0 (audible)

/XCTRL0:<0,1>  XCTRL0 Pin set        System specific.  Sometimes used to

/XCTRL1:<0,1>  XCTRL1 Pin set        control power to amplifier.  On IBM

                                     Aptiva with Bose speakers, set both to 1



/P:<port>      Codec Port            *534, 608, (530..FF8, divisible by 4)

/I:<irq>       Codec IRQ             *5, 7, 9, 11, 15 (decimal)

/D:<pDMA,cDMA> Codec DMA             0, 1, 3 (Default 1,0)

/C:<port>      Control Port          120, *538, (120..FF8, divisible by 8)

/J:<port>      Joystick Port         *200, 208, NONE

/S:<port>      Sound Blaster Port    *220, 240, 260, 280, NONE

/M:<port,irq>  MPU Port and IRQ      *330, NONE, (300..3E0, divisible by 8)

                                     IRQ: 7, 9, 11, 12, 15, *NONE

/F:<port>      FM synth port         *388, NONE, (388..3F8, divisible by 8)



/IRQRate:dd    Target interrupt rate *32  Range: 1..64 interrupts per second

/DMASize:nnnn  DMA Buf size maximum  *8192 Range: 256..16384 (2 IRQs/Buffer)

                                     





CWVAUDIO.SYS   - OS/2 audio virtual device driver.



Option/Format  Description               Valid Values (* = Default Value)

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

               Name of PDD              Supplied by install program (*BSAUD1$)

/S             Skip DOS Envir Var Scan  (*not enabled)





OPL3.SYS       - IBM FM/OPL-3 MIDI Synthesis Physical Device Driver



/P:nnn         Base I/O: Sets the base I/O address for FM device.

               Is almost always, 388 (nnn is in hex)







7) Notes on Command Line Options

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



 CWVAUDIO.SYS /S Option:

 The CWVAUDIO.SYS driver will automatically set a 'BLASTER' DOS environment

 variable to the proper audio hardware settings.  This is done by adding a

 '@SET BLASTER=' line to the beginning of all DOS session's autoexec file.

 This file is specified in DOS session's DOS_AUTOEXEC property.  The /S option

 for CWVAUDIO.SYS will skip the automatic setting of this environment variable.





8) Using Audio in DOS and Win-OS/2 Sessions

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

Crystal Semiconductor device drivers provide outstanding support for WinOS2.



- Crystal Windows drivers are automatically installed for WinOS2 use.

- Crystal Windows drivers are OS/2 aware and communicate with OS/2 audio

  drivers to manage concurancy issues.





For most users, this support prevents concurancy related errors from

occuring.  Still, they can occur.  Some details on concurancy and

other tips for WinOS2 and DOS game execution follow:





The installation automatically configures WinOS2 Audio when you install Crystal

Audio drivers.  Windows audio drivers are installed for OS/2 Fullpack systems

only.  OS/2 Red Box systems which use the Microsoft Win 3.1 binaries will use

the Crystal Audio Windows 3.1 drivers that are used in native DOS/Win 3.1.

In either installation case, the Crystal Audio drivers used for WinOS2 are

the same.  That is, there is no special set of drivers for WinOS2.



The Crystal Windows 3.1 drivers are OS/2 aware and when loaded under WinOS2

communicate with the OS/2 Physical Device Drivers to negotiate access to

the audio device.



To enable game processing, the following DOS properties are commonly set.

This is not done automatically by the installation.  Many of the below

DOS properties default to the correct settings.



    WIN_RUN_MODE                 3.1 ENHANCED COMPATIBILITY

    AUDIO_ADAPTER_SHARING        Required

    INT_DURING_IO                On  ( This is the most critical setting )

    HW_TIMER                     On

    VIDEO_SWITCH_NOTIFICATION    On

    VIDEO_8514A_XGA_IOTRAP       Off

    VIDEO_RETRACE_EMULATION      Off ( This setting critical for graphics )

    DPMI_MEMORY_LIMIT            8





9) Audio Concurrency Issues - OS/2, DOS, Win-OS/2

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



When you have a single audio device, it is not possible for two programs

to use the device at the same time.  For example, if one application has

the device configured for audio playback, and a second application

also wishes to perform audio playback, a conflict exists.



The OS/2 multimedia subsystem (MMPM/2) is designed such that, when an

application is running in the foreground (has focus), then that application

takes priority over others running in the background.

MMPM/2 manages the device contention, forcing pauses and resumes to

pass use of the device to the current focus application.



This robust support is only available for OS/2 native applications.



When DOS games or WinOS2 drivers try to use the device, MMPM/2 is not

involved and cannot force an application off the device.  When the DOS

environment is using the audio device, MMPM/2 is locked out.

This creates an opportunity for contention.



To minimize the impact of this problem, Crystal Semiconductor's WinOS2

drivers are OS/2 aware.  They communicate with their OS/2 counterparts

to release use of the device at all times when WinOS2 is quiet.

This is a vast improvement versus many other OS/2 device driver sets.



When WinOS2 is quiet, it is "idle" and will not prevent MMPM/2 or other

WinOS2 or DOS sessions from using the device.  This also allows you to

run multiple separate WinOS2 sessions with no concern of audio sharing

between the sessions.



MMPM/2 by contrast considers the device "busy" when ever an OS/2

multimedia application is loaded.  For example, loading the OS/2 shipped

Digital Audio player will prevent WinOS2 from using the audio device.

This is often not an issue as the most prevalent OS/2 multimedia

application, system sounds, releases the device after each sound is played.



DOS games are unaware of other entities in the system and

do not respond well to being kicked off the device.

A running DOS game will prevent OS/2 and WinOS2 from using the audio device.





For more information on this subject, see OS/2 online documentation



    VIEW /AUDIO

    VIEW /MULTIMEDIA

    VIEW /SOUNDS





10) Plug and Play System Issues

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

PnP configuration is used to assign IRQ/IO/DMA resources to the Crystal

audio device.



The following entities can perform PnP configuration:



1. OS/2 Warp 4.0 configuration manager.  Warp 3 is not PnP aware.

2. PnP ISA BIOS - common on desktop computers

3. PnP BIOS System device node - common on notebook computers

4. Crystal audio driver can perform its own PnP initialization.



The final device settings are based on a set of default values

in the device driver.  The driver communicates with the operating

system and BIOS at boot to receive information on how these

entities may have configured the audio device.

Finally, the driver supports command line overrides so that

the user can specify a particular set of resources.



Where the final settings are different from the BIOS/OS settings,

the device driver performs its own PnP sequence to configure the

audio codec.



The use of overrides should not be necessary as the assignment of

resources to devices is a responsibility of the operating system and

system BIOS.  While OS/2 Merlin is a PnP aware OS, it provides no

means for a user to override an OS assigned resource.   This makes

support of device driver overrides a necessiry.



Additionally, the Warp 4 OS does not (by default) perform a full

PnP isolation on each boot.  It is possible for discrepancies

to arrise where the OS database of installed devices does not

match the hardware that is actually installed.  This will result

in incorrect information being provided to the device driver at

initialization.  You can command an OS/2 full PnP sequence by

pressing Alt-F1 early in the boot sequence and selection option, F5.



The audio driver follows the sequence below for PnP initialization.



1.  Crystal audio device driver has default values

2.  PnP ISA BIOS is queried to see if it has configured the audio device.

3.  Warp 4 PnP manager may specify values that it has assigned.

4.  PnP BIOS is queried regarding system device nodes (notebook computers)

5.  User supplied command line parameter override Warp and BIOS PnP settings





11) Mixer Issues

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

As of this release, there is no generic OS/2 mixer application.

Therefore, the volume control for devices attached to mixer LINE, AUX1,

and AUX2 is established on the command line of the CWAUDIO.SYS driver.

Refer to section 6, CWAUDIO.SYS, for the format of the unmute and gain

setting  options.



These values for gain are set on each boot and cannot be altered during system

operation.  The command line values represent a percentage range 0..100 where

0 is mute and 100 is maximum volume.

NOTE: This is different than the format of these parameters in earlier

version of the Crystal audio drivers where the settings were dB attenuators.



The devices attached to LINE, AUX1, and AUX2 are system dependent but

generally reflect CD-ROM audio playback and sound card line-in jack.

Refer to your system documentation for device configuration.

With the default installation, all inputs are un-muted - which makes CD-ROM

audible.



Note:  These settings do not effect standard wave audio volume or record

source and gain which are controlled by the OS/2 volume control icon and

application sliders.





12) DMA Buffer size and interrupt rates

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

The Crystal audio device is a direct memory access (DMA) based audio codec.

Audio data is placed into the DMA memory buffer and then when needed, it

is extracted to the audio codec without action by the CPU.



DMA buffer size and interrupt rate are inversly related.  The smaller

the DMA buffer, the higher the interrupt rate.  The audio device 

generates 2 hardware interrupts for each full DMA buffer.



Small DMA buffers (high interrupt rates) are needed for applications 

like software motion video and large DMA buffers are desired for high 

datarate applications including playback or record of 16-bit 44K stereo.



Curiously, the audio buffers that the device driver receives from

the operating system vary in size.  There is no information provided

to the audio driver to let it know what size buffers will arrive.

The audio driver must size the DMA buffer when a stream starts and

must size the buffer based only on type of data and data rate.



For games, the MMPM/2 DART API allows the game developer to specify

the size of data buffers which will be provided to the audio driver.

Again, this information is not relayed to the audio device driver.

Some DART games require DMA buffer sizes which can be at most 4KB.

Sizing the DMA buffer to support these applications may break 

other applications which require larger buffers (CD Audio streaming)



The calculation of DMA buffer size is primarly based on desired 

interrupt rate.  The interrupt rate must exceed the frame rate of 

software motion video.



The Crystal audio device driver defaults to a DMA buffer size and

interrupt rate that supports the vast majority of applications.  

Still, there are some applications that have particular needs which 

are not served by the default selections.



To support cases where the default settings do not work, the driver

supports /DMASIZE and /IRQRATE command line parameters.  



The default settings for IRQRATE and DMASIZE are:

     32 Interrupts per second nominal rate.    Range 1..64

   8192 Maximum DMA buffer size (2 IRQs per full buffer) Range 256..16384



The driver attempts to maintain 32 (IRQRATE) interrupts per second.  It

should be noted that the interrupt rate must be greater than the frame

rate for software motion video.  DMA buffer size is calculated based

on desired interrupt rate and the physical size limits of DMA buffer.



For example: Playback of a system sound, startup.wav

   11025 Sample rate

     * 8 Bits per sample

     * 1 Channel

     / 8 Convert count of bits to count of bytes

   -----

   11025 Bytes per second



   Bytes per interrupt = 11025 / 32 => 344

   Bytes for DMA buffer = 344*2 => 688 Bytes.



Notice that while DMASIZE defaults to 8KB, only 688 bytes are used

for playback of this file.



Another example: Playback of CD quality data (CD digital transfer)

   44100 Sample rate

    * 16 Bits per sample

    *  2 Channels

     / 8 Convert to count of bytes

   -----

  176400 Bytes per second



   Bytes per interrupt = 176400 / 32 => 5512

   Bytes for DMA buffer = 5512*2 => 11024 Bytes.

   Since 11024 is greater than 8192 (DMASIZE), the DMA buffer is 

   restricted to a length of 8192 bytes.

   Resulting interrupt rate is 17600/8192 = 43 IRQs/Second.



The target interrupt rate and DMASIZE variables in this equation

can be overridden via command line options.





13) MIDI Synthesis

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

This installation diskette includes support to install the IBM OPL3

device driver.   All of the Crystal Semiconductor audio codecs which

support this device driver include an integrated FM synthesizer.



The installation pre-selects the IBM OPL3 driver and will install

it unless you de-select this item.



You may find that the default FM playback volume is too high or too low.

The output of the FM part is routed through the Crystal Audio CODEC and

its gain/attenuation can be adjusted by changing mixer command line

options on the CWAUDIO.sys audio device driver.





14) MPU-401 - Wavetable installations

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

This section is only applicable if you have MIDI instruments

connected to your computer or if you have a sound card with

hardware wavetable support.



A note about having Multiple MPU-401 Devices:



To locate MPU-401 hardware, the driver CWMPU401.SYS uses a 

port-scanning technique to find the base I/O address for the MPU-401 

hardware on the sound card.  If there is another MPU-401 device in 

the computer, the MPU-401 driver could detect and use that device 

instead of the one on the sound card.  If this does occur, you 

can perform the following actions to solve the problem:

- Determine what the base I/O address is for the MPU-401 device.

  For example, say it's 340.  On the DEVICE=...\CWMPU401.SYS line,

  replace the "/O:ONLYONE" with "/P1:340".





15) Web Site - where to get updated drivers

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

This device driver supports the following Crystal Semiconductor CODECS:

   CS4236B, CS4237B, CS4238B, CS4235, CS4239

These parts are "mode 3" capable.



This device driver should not be used for:

   CS4231, CS4232, CS4236

These parts are "mode 2" capable.  Please get the version 1.xx driver

from the Crystal Semiconductor web site: http://www.crystal.com





16) Special notes on upgrading from driver version 1.xx to 2.xx.



The Crystal Audio driver included in this package has been

significantly enhanced to utilize Crystals "mode 3" codecs.



The driver provides the following enhancements:

a) Supports Crystal "mode 3" audio CODECS:

      CS4236B, CS4237B, CS4238B, CS4235 and CS4239



   CS4231, CS4232, CS4236 customers should use driver version 1.7x

   which is available on the Internet:

      http://www.cirrus.com/drivers/audiodrv/



a) Full duplex play and record of independent data formats at

   independent sample rates.  On prior driver, the data format

   could be different, but the same rate had to be the same.



b) Support for INPUT Mixer.

   Crystal mode 3 codecs can mix input sources in the same

   manner that other devices can mix output signals.

   That is, multiple input sources can be active at one time.

   The signal recorded is the summation of all the selected sources.



   OS/2 API is however input "mux" (mutially exclusive) orientated.

   It provides the ability to select record sources "Line-In" and "Mic".



   On past device drivers, the logical concept of "Line-In" has defaulted

   to codec input Aux-2.  This did not work for all people as the

   assignment of signals to codec (chip) inputs is board specific.

   To work around board specific issues, the driver provides a

   command line switch to specify the assignment of "line-in".



   The new driver is able to associate Line-In to the summation of

   Aux-1 and Aux2 which will work in most cases for CD-Audio record.

   Where necessary, the logical to physical mapping of "Line" can

   be specifically stated with the (/LCAPT:).



c) Warp 3 FixPack 26 detection during install ( Warp 3 only )

   Some Warp 3 users have noted that Warp 3 fixpack 26 has OS/2 DART

   support which is better than the DART support installed with prior

   versions of the Crystal installation.   We have historically

   installed MMPM/2 DART DLLs which came from the Developers

   Connection DART CD-ROM.  (ampmxmcd.dll and audioif.dll)

   The Developers Connection version of these DLLs is slightly older

   than the DART support included with MMPM/2 in fixpack 26.



   To accommodate both Warp 3 FP26 users and Warp 3 no-fixpack users,

   the Crystal installer has been updated to auto-detect FP26 and

   install DART DLLs appropriate to the service level of the target system.



   All files replaced during installation are backed up before being replaced.

   Check file \mmos2\install\minstall.log for details on actions taken

   during installation.



   Warp 4 (Merlin): The Crystal installer checks OS/2 version and only

   performs the system component updates on Warp 3 systems.



16) Problems/Questions

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

Please e-mail problems/questions to the following address:

montalvo@crystal.cirrus.com

