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Introduction to C/MS Interface.


CT-VOICE.DRV is a program loadable driver that provides the
basic voice interface functions for most of the high level
languages under the DOS environments.

To use these functions, the calling program has to load this driver
at the offset zero of a segment. All functions are invoked by a call
to the offset zero of the segment where the driver is loaded.

To verify that the file loaded is a voice driver, the calling program
must check at the offset 3 location to make sure that the driver
ID - "CT-VOICE" is there.

Parameters are passed through the various registers between the
calling program and the driver. The use of registers is as follow:

    Register BX.

  This register contains the function number to invoke. It
  must be setup before the call.

    Other registers.

  These registers usually are used for general data of byte
  or word type. AX is also used as return address for the
  return value in byte or word. If return value is a long
  data type (4 Bytes), it will be returned in DX:AX.

  Except for the register AX and DX, all other registers are
  preserved, including the flags registers.