                           Release Notes for
                     IBM Power PC Audio Device Driver
                        (Version 1.04 - 04.26.96)


1. Description of IBM Power PC Audio Device Driver

    The IBM Power PC Audio Device Driver (i.e., the driver) is a Windows NT
    driver that consists of the following components:

        - Kernel Mode device driver
        - User Mode device driver

    The Kernel Mode device driver component is a lowest-level driver that
    supports the Crystal 423x series of Audio CODECs (i.e., it directly
    reads and writes the CODEC registers and provides the Interrupt Service
    Routine for the device). It provides the following features:

        - supports multi-threading (concurrent use of multiple WIN32
          multi-threaded applications)
        - multi-processor safe
        - full duplex operation (play and record simultaneously)

    The Kernel Mode driver requires two DMA adapters and one IRQ. The driver
    makes use of the AutoInitialize mode of the DMA services in conjunction
    with a double buffering scheme and the playback and capture counters
    internal to the CODEC chips. The Kernel Mode driver is modeled after the
    SNDBLST Kernel Mode driver in the standard Windows NT DDK. It makes
    extensive use of the SOUNDLIB library, which is also part of the standard
    Windows NT DDK.

    The following logical devices are supported:

        - WaveIn   [low-level capture functions of the multimedia API]
        - WaveOut  [low-level playback functions of the multimedia API]
        - Mixer    [mixer functions of the multimedia API]
        - Aux      [auxiliary functions of the multimedia API]

    Detailed information related to a Kernel Mode device driver can be found
    in the Kernel Mode Driver Design Guide in the MS Developers Network
    documentation.

    The User Mode device driver is a WIN32 Subsystem driver that provides
    the API to the Kernel Mode driver for the WIN32 Subsystem. It provides
    support for multi-threaded applications. Through the use of DRVLIB in
    the Windows NT DDK, the User Mode device driver provides standard support
    for WINMM.

    Detailed information related to a User Mode device driver can be found
    in the Win32 Subsystem Driver Design Guide and the MS Developers Network
    documentation.

    The IBM Power PC Audio Device Driver was developed at the IBM Kirkland
    Programming Center (KPC) in Kirkland, WA.

2. System Requirements

   The IBM Power PC Audio Device Driver supports the following IBM Personal
   Power systems:

        System ID     Code Name      OS                 CODEC
        ---------     ---------      --------------     ------
        IBM-6070      Carolina       Windows NT 4.0     cs4232
        IBM-6015      Sandalfoot     Windows NT 4.0     cs4231
        IBM-6042      Woodfield      Windows NT 4.0     cs4231
        IBM-6040      Wiltwyck       Windows NT 4.0     cs4231
        PowerStack    PowerStack     Windows NT 4.0     cs4231
        IBM-7042      Tiger          Windows NT 4.0     cs4232

    The IBM Power PC Audio Device Driver supports the following ISA audio
    cards on the IBM Personal Power systems:

        - Crystal 4232 reference card

3. Installation of IBM Power PC Audio Device Driver

    The IBM Power PC Audio Device Driver is comprised of the following
    files:

    - cs423x.sys    [Kernel Mode device driver]
    - cs423x.dll    [User Mode device driver]
    - cs423x.hlp    [Windows NT Help file]
    - oemsetup.inf  [Installation and setup file]
    - release.txt   [This file]
    
    The above files can be found at the following locations:

    - Internal KPC Network  [contact your network administrator at KPC]
    - FTP site              [contact your IBM Windows NT support personnel]
    - BBS site              [contact your IBM Windows NT support personnel]

    If you access the BBS or the FTP site, use a floppy disk or your local
    hard disk to save a copy of the IBM Power PC Audio Device Driver files.

    The following describes the installation procedure on a Windows NT 4.0
    system:

        1. Insure that your computer is included in the list of supported
           systems (see section 2 above). IF YOUR SYSTEM IS NOT INCLUDED
           IN THE LIST, DO NOT ATTEMPT TO INSTALL THE DRIVER.
        2. Remove all previously installed Audio drivers through the
           Control Panel - Multimedia Applet. Examples are:
               - cs4231    [IBM Business Audio]
               - ppc4231   [IBM Power PC Audio]
               - ppc4232   [IBM Power PC Audio]
               - sndblst   [Creative Labs SoundBlaster]
               - mvaudio   [Media Vision Pro Audio Spectrum/Thunderboard]
               - Windows Sound System
        3. Reboot your computer
        4. Remove all previously installed Audio driver files. Check the
           following filesystem locations:
               - %SystemRoot%\System32
               - %SystemRoot%\System32\drivers
        5. If necessary, remove all registry references to previously
           installed drivers. Check the following registry locations:
               - HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
        6. Install IBM Power PC Audio Device Driver through the 
           Control Panel - Multimedia Applet. Go to the tab labeled
           'Devices'. Select the 'Add' button. Select 'Unlisted or
           Updated Driver'. Specify the location according to the
           sites or storage medium mentioned above.
        7. Reboot your system.

4. Known Problems

    a. Problem if you cancel the properties dialog box of the sound drivers
       when the mixer applets is open.
    b. (1. change format/2. start a DMA output transfer/3. stop the transfer/4. go to #1)
       After a number of iterations of the above procedure (sometimes few,sometimes many), 
       the 4232 chip seems to go into an inoperative state that
       requires a reboot of the system, though not necessarily a power off. The
       problem does not appear with the CS4231.

5. Possible Future Development

    - Power Management
    - Intel HW platforms
    - ISA bus Audio cards featuring the Crystal 423x series Audio CODECs
    - Ameliration of IBM SoftMidi installation 
 -  - Having made contact for more information about bug 39759.

6. Differences from previous revisions of IBM Power PC Audio Device Driver
 
    a. Made Tiger supported
    b. Made changes for PowerStack (CS423x.c) The XCTL1 bit actuates a relay in 
       the Comet boards that enables sound to be output to the line out jack.
    c. Fixed midi problems (couldn't play two wave files, or a midi and a wave file) 
       in cs423xMixerInit.
    d. Added cs423xWaitForDRQ (when we are ready to stop DMA of playback, we poll the DMA status register 
       until the DMA Request line is high. Then, we reset PEN.) for bugs 39759. 
    e. Changed in mix_obj.c controls from 2 -> 1 for SourceMuxAux1
    f. Deleted PeakMeter for Record and, added peakmeter for all selection. 

7. Revision History

    Version 0x0104    User - Added Tiger in the supported machine.
                      Kernel - Made change for PowerStack to actuates a relay.
                             - Fixed midi problems.
    			     - Seems to make the problem 39759 happens later.
                             - Fixed case 11, 12, 13, 20 of bug 44759.

    Version 0x0103    User - (GetChipType line 156) Fix for WoodFieldPrime.
                      Can cancel on a Sandalfoot after changing volume settings. 

    Version 0x0102    Wave Format change error fix
                      kernel - cs423xSetFormat() in cs423x.c line 867
                      Saved Mixer Settings in cs423xShutdown() in dvcentry.c line 626
                      New Settings Dialog in cs423x.dll
                      Sound Icon on taskbar, multimedia applet volume control

    Version 0x0101    CS4231 Master Volume and Mute, sound card support
                      kernel -
                      localmix.h, mixdvc.c, sources, release.txt,
                      config.c, cs423x.c, dvc423x.h
                      cs4231SetOutputAttenuation(), cs4231SetOutputMute()
                      Configuration dialog, sound card support
                      user -
                      config.c                      

    Version 0x0100    The initial release of the IBM Power PC Audio Driver.
                      All files - kernel mode and user mode.


