Re: [linux-sunxi] Buffer size limitations in sound device?
Ok thanks for the reply. I now see that I have omitted the info that I am already using Alsa, and the "the buffer to 8192 periods, now 4" should of course read "the buffer to 8192 frames, now 4 periods". Sorry for the confusion. I will try to find out how I can install "emilio's kernel" and see if that fixes the problem. I am an experienced Linux user but new to CubieBoard2. -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: [linux-sunxi] Buffer size limitations in sound device?
There is no hardware limit. The audio buffer is in main memory. If the driver is properly written you should be able to use ALSA to allocate a larger buffer. Try emilio's kernel. It has 192/24 working and I believe it should work to allocate arbitrary buffers but I haven't tried. On Thu, Oct 16, 2014 at 5:31 AM, Rob wrote: > I am trying to use the on-board analog sound output on a CubieBoard2 (A20) > with a program that I developed on the PC platform. > > It uses 16bit 48000 samples/s stereo audio output, and tries to set a 16384 > frame > buffer (16 periods of 1024 frames). > > The driver on the CubieBoard2 (from the current version of Cubian) refuses > this > setting and limits the number of periods to 8 and the buffer size to 8192 > frames. > > I can find the 8-period limit in the driver source that I retrieved using > git clone -b sunxi-3.4 --depth 1 > https://github.com/linux-sunxi/linux-sunxi.git > (I'm not completely certain that this is the source of the kernel I am > running). > > Is it a hardware-determined limitation? > However, when I change my program to use 2048-frame periods, it still limits > the buffer to 8192 periods, now 4. > > I wonder if there is some way to get around this, or if this is a hardware > limitation that can not be fixed in the driver (and so I will have to change > my program to work around having the smaller buffer)? > > Rob > > -- > You received this message because you are subscribed to the Google Groups > "linux-sunxi" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to linux-sunxi+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- Jon Smirl jonsm...@gmail.com -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
[linux-sunxi] Buffer size limitations in sound device?
I am trying to use the on-board analog sound output on a CubieBoard2 (A20) with a program that I developed on the PC platform. It uses 16bit 48000 samples/s stereo audio output, and tries to set a 16384 frame buffer (16 periods of 1024 frames). The driver on the CubieBoard2 (from the current version of Cubian) refuses this setting and limits the number of periods to 8 and the buffer size to 8192 frames. I can find the 8-period limit in the driver source that I retrieved using git clone -b sunxi-3.4 --depth 1 https://github.com/linux-sunxi/linux-sunxi.git (I'm not completely certain that this is the source of the kernel I am running). Is it a hardware-determined limitation? However, when I change my program to use 2048-frame periods, it still limits the buffer to 8192 periods, now 4. I wonder if there is some way to get around this, or if this is a hardware limitation that can not be fixed in the driver (and so I will have to change my program to work around having the smaller buffer)? Rob -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
