update the library to differentiate between "not recommended" vs "can't
do". update DSP play start code to use the "can't do" function to
determine if it cannot start playback. added "idle" function call. this
idle function call will blindly read the status registers to clear any
IRQs coming from the card if the card context was configured without any
IRQ. Added notes on what the Sound Blaster 16 non-PnP mixer
configuration byte means. Also noted the Sound Blaster 16's logic in
halting DMA transfer if the host doesn't ack the interrupt (where clone
cards would keep going), which is the reason for the idle call.
Capability updates now permit TEST.EXE to play back 16-bit audio with no
IRQ and no 8-bit DMA channel assigned, or to do DMA-based playback
without any IRQ whatsoever.
update test.c to allow 16-bit DMA channel to be set to 0,1,3 (but with
logic for non-PnP SB16 that the channel must be 5,6,7 or match 8-bit
DMA). added call to idle function. added command line option to disable
calling the idle function.
update code to clarify limits, sample rate ranges, what is not
recommended vs what is not possible.
port idle and /noidle code to playmp3