Subject: Re: es1371.o sound module on a IBM405 gp walnut

From: David Blythe <[email-masked]>
Date: Sun, 18 Mar 2001 20:58:06 -0800

Ralph Blach wrote:
>
> I am trying to get an es1371. sound module working on an IBM405 walunt
> developement kit.  8 bit sound works ok
> but 16 bit sound sounds like noise.  Will this driver have to be made
> Endian  aware?

Yes and no.  A lot of the player programs are not very endian savy.
Typically what I have seen happen on bigendian ppc is that either the
player asks for AFMT_S16_LE  but really sends  AFMT_S16_BE samples and
you get noise (sox/play does this but I worked on a patch for this with
Chris Bagwell so hopefully it is available now) or it asks for
AFMT_S16_BE samples and the driver doesn't support this and the request
format ioctl defaults to AFMT_U8 instead and the player ends up sending
8 bit samples instead of 16, because it didn't also do a query for
AFMT_S16_LE.  An earlier version of madplay was doing this (I tooked the
easy way out and had our sound driver return AFMT_S16_LE as the default
format to get around this, but the query algorithm in madplay could be
made better).  It looks like the es1371 driver defaults to AFMT_U8.
	david

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