From owner-freebsd-multimedia Tue Sep 9 08:41:03 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id IAA15777 for multimedia-outgoing; Tue, 9 Sep 1997 08:41:03 -0700 (PDT) Received: from labinfo.iet.unipi.it (labinfo.iet.unipi.it [131.114.9.5]) by hub.freebsd.org (8.8.7/8.8.7) with SMTP id IAA15767 for ; Tue, 9 Sep 1997 08:40:51 -0700 (PDT) Received: from localhost (luigi@localhost) by labinfo.iet.unipi.it (8.6.5/8.6.5) id QAA19260; Tue, 9 Sep 1997 16:30:29 +0200 From: Luigi Rizzo Message-Id: <199709091430.QAA19260@labinfo.iet.unipi.it> Subject: any experience with sb16 and fullduplex ? To: multimedia@freebsd.org Date: Tue, 9 Sep 1997 16:30:28 +0200 (MET DST) Cc: luigi@labinfo.iet.unipi.it (Luigi Rizzo) X-Mailer: ELM [version 2.4 PL23] Content-Type: text Sender: owner-freebsd-multimedia@freebsd.org X-Loop: FreeBSD.org Precedence: bulk I know probably noone has the answer but... does anyone have experience with the SB16 used in full duplex ? I am doing some tests with vat here and although I have it working, let's say that it does not behave as I expect... e.g. the only way I currently managed to make things work is to use signed formats on both channels, e.g capture AFMT_S8, playback AFMT_S16_LE or capture AFMT_S16_LE, playback AFMT_S8 I wonder if anyone is aware of restrictions in the use of the card in full duplex. I have a program dated 1994 downloaded from the Creative www server which uses the card in full duplex, with a big disclaimer that it might not work on future cards etc.etc. and does the following: * This program does a 16-bit recording to disk, then after about 1 second * starts an 8-bit playback from the same file. The recording format is * 16-bit signed. For playback, the low byte of each sample is discarded to * convert it to 8-bit signed. (Note that the usual format for an 8-bit * recording is UNsigned. I programmed it for 8-bit signed for avoid the * unsigned to signed conversion.) I am not sure the use of signed format on both channels is just a matter of convenience or it serves to circumvent some limitation in the hardware... Anyways it seems to work, and possibly tonight I will make another snap for the impatients. Cheers Luigi