        Full Dulpex Wave Driver Version 3.50 
                      for
                Sound Blaster 16

Introduction

The Sound Blaster 16 wave/midi driver, sb16snd.drv, is modified to support
simultanteously recording and playback.  This feature is requested by a lot
of development for implementation of audio conference application. 

This driver is modified from the Sound Blaster 16 Version 3.06 source code.
The interface between CSP manager and ACVs are also modified to support the
multiple instant. CSP Manager is modified to support sample conversion from
16-bit to 8-bit or vice versa.   All ACVs are modified to support new
interface between CSP manager and ACV.


Features:

Beside the normal multimedia wave and midi port function,  the full duplex
wave driver supports the following additional features:

*	simulatanteous recording and playback with same sampling rate
*	both playback and record can be either mono or stereo 
*	both playback and record can be either 16-bit or 8-bit wave file
*	playback and record of both 16-bit or 8-bit are also support


Software List

This wave driver (sb16snd.drv) require a newer version of CSP Manager
(version 3.50 and above) and ACVs (version 4.00 and above).  The software
list is:

    sb16snd.drv   ver.3.50    Full Duplex wave driver
    cspman.drv    ver 3.50    new cspman support multiple instance
                              and sample conversion
    wfm0006.acv   ver 4.00    new Alaw ACV for CSPMAN 3.5
    wfm0007.acv   ver 4.00    new Mulaw ACV for CSPMAN 3.5
    wfm0011.acv   ver 4.00    new IMA ADPCM ACV for CSPMAN 3.5, new data
                              packaging (see comment in IMA ADPCM)
	wfm0200.acv   ver 4.00	  new CT ADPCM ACV for CSPMAN 3.5
	wfm0201.acv   ver 4.00	  new Text2Speech ACV for CSPMAN 3.5
	wfm0202.acv   ver 4.00	  new FastSpeech 8  ACV for CSPMAN 3.5
	wfm0203.acv   ver 4.00	  new FastSpeech 10 ACV for CSPMAN 3.5

	
	wfm0011a.csp  ver 4.00	  new IMA ADPCM Codec with new data packaging
	wfm0202a.csp  ver 1.01	  new FastSpeech 8 (some bug fixes)
	wfm0203a.csp  ver 1.01	  new FastSpeech 10 (some bug fixes)

Note that the new *.ACV and *.CSP is same as in Win95 version.  The wave
and midi driver (sb16snd.drv) only work with CSPMAN version 3.50 and ACV
version 4.00.  



IMA ADPCM 

Microsoft has modified the way of packing the wave data for IMA ADPCM in
Win95 and ACM version 2.04 and above. The IMA ADPCM ACV version 4.00 follows
the new way of data packing and is not compatiable with the older version.
The IMA ADPCM wave file that recorded using the older version of wave driver
and ACV (ver. 3.0x) will not playback correctly in this new wave driver.

Both ACV (wfm0011.acv) and CSP (wfm0011a.csp) file are changed to reflect
these changes.  



Installation

Backup your drivers, ACVs and CSP before installation. For testing purposes,
you will only need to copy the drivers, ACVs and CSPs to respective
directories as follows:

                copy to
    sb16snd.drv windows\system
    cspman.dll  windows\system
    *.acv       windows\system
    *.csp       sb16\csp
                (if your sound=c:\sbawe, then copy to c:\sbawe\csp)



Full Duplex Requirements

In order to do a playback and recording simultaneously, the following
restrictions apply:

1. Both operations must be of same sampling rate.
2. Both operations must be in PCM format, ie., no compression.
3. VSBPD.386, the enhanced mode virtual device driver, must be present.
4. Both High and Low DMA channels are required, so both channels must be
   available at the same time.


