Troy Kisky wrote: > Hi All > > > I'm using the TLV320AIC23 to record sound from a mic. It sounds fine > when I play it back, but when I look at the data, the value > in one channel is always exactly double the value in the other. > Since the mic gives the same input to both ADC's I was expecting > to have the same value in the left & right channels. Has > anyone seen this before? Any guesses to what I might be doing > wrong? Can someone using an AIC23 check their data for me? > I'm using a davinci DM644x platform and spi interface to the codec > in dsp_a mode. > > > > sample data > 00ec40 fffeffff 00040002 00040002 00000000 > 00ec50 fffeffff fffeffff 00000000 fffafffd > 00ec60 fffeffff 00020001 00040002 00080004 > 00ec70 000a0005 0016000b 0014000a 001a000d > 00ec80 001c000e 001e000f 00200010 00260013 > 00ec90 001e000f 001e000f 001e000f 001c000e > 00eca0 001c000e 0018000c 0014000a 0014000a > 00ecb0 0014000a 000e0007 00120009 0014000a > ^ ^ ^ ^ > Always even > > > After swapping the left & right channels > at the codec > > 011af0 fffcfffe fffeffff 00060003 00060003 > 011b00 000a0005 000c0006 000e0007 000c0006 > 011b10 00080004 00080004 00060003 00060003 > 011b20 00080004 00060003 00060003 00040002 > 011b30 00020001 00020001 00000000 00020001 > 011b40 fffeffff 00000000 00040002 00060003 > 011b50 000c0006 000e0007 00100008 0014000a > 011b60 00120009 000e0007 00100008 00100008 > 011b70 000e0007 00080004 00080004 00060003 > 011b80 00060003 00060003 00060003 000a0005 > > > No change, so the ADC's both do convert to > the same value. But there appears to be a 1 bit > delay between the two channels. > > My McBsp is reading 1 32 bit element, so I don't > think it can shift only half of the element. > > > > After switching to dsp_b mode (an extra bit > delay before data starts) > > 00b130 fff8fff8 fff5fff5 fffafffa fffcfffc > 00b140 fffefffe 00010001 00000000 00010001 > 00b150 00020002 00010001 00010001 00010001 > 00b160 00000000 ffffffff 00020002 00000000 > 00b170 00000000 00000000 fffefffe fffefffe > 00b180 fffdfffd fffdfffd 00000000 ffffffff > 00b190 00020002 00010001 00020002 00030003 > 00b1a0 00030003 00030003 00050005 00030003 > 00b1b0 00050005 00030003 00010001 00000000 > > When I play this back in dsp_b mode I hear > random soft popping from the speaker, but it is loud. > > Playing it in dsp_a mode is quiet with no popping. > > So, I conclude that recording with the codec is buggy > in dsp_a mode and playback is buggy in dsp_b mode. > I hope someone will tell me I'm wrong. > > Thanks > Troy I just tried the same code on a different board of the same type, and it is working fine. So, please excuse the noise. Troy _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
