Clive Wright kirjoitti: > [EMAIL PROTECTED] wrote: > >> Hi all, >> >> I'm currently hacking around in kmix to add at least basic OSS4 support. >> I've >> got an usb device with a output.vol control with a value range of 0 - 37. I >> of course get values much higher than that when reading from the mixer >> device. The normal procedure as shown in the doc and in the ossmix source is >> to clamp (is that the right word?) with a bitmask. >> >> According to the documentation the value is a 31 bit positive integer, >> therefore the bitmask should be 0xFFFFFFFE - but that would be wrong, >> because >> I'd get values of about 9k, whereas I need 0 - 37, which I get when using >> the >> bitmask 0xFF and AND the value with it. >> What's wrong here, me or the documentation? >> >> > > If control is graduated in centibels required range is probably 0 to 370 > whereas kmix is probably 0 to 100 so you will have to apply a scaling > factor (kmix * 37 / 10 = ossmix). Ideally mixer should read max. value > and scale accordingly. > The driver should return maxvalue=370 in that case. The value returned for a any of the channels should never be higher than the maximum value.
Best regards, Hannu _______________________________________________ oss-devel mailing list oss-devel@mailman.opensound.com http://mailman.opensound.com/mailman/listinfo/oss-devel
