6 Nov
2006
6 Nov
'06
5:07 p.m.
Although I am very satisfied with the pressure I was
able to create, I
do feel obliged to point out there is probably more wrong with my device
than the low volume.
The volume setting test program is now functional. I haven't tested it
listening to the output or input because I don't have a working
environment right now but from what I see what's going on it looks good.
wagi@newton:~/src/libfreebob/tests$ ./test-volume 0 1 -1000
max volume value = 0
min volume value = -32768
old volume value = 0
new volume value = -896
"The min and max attributes can range from 127.9922db (0x7ffe) down to
-127.9961 dB (0x8001) in steps of 1/256 dB or 0.00390625 dB (0x0001).
Code 0x8000 represents silence." AV/C Audio Subunit Specification 1.0
In reality the max value seems to be 0 (0 dB) and the minimum value
-32768 (-inf dB, silence). The firmware will round the to something
meaningful.
The FA-101 has only input feature function blocks. So you can't control
the output level directly. I guess one can control that with the mixer
(missing feature).
wagi@newton:~/src/libfreebob/tests$ ./test-volume
usage: NODE_ID FFB_ID VOL
Feature function blocks ids for the FA-101:
Id 1: Input 1/2
Id 2: Input 3/4
Id 3: Input 5/6
Id 4: Input 7/8
Id 5: Input 9/10
The default values for the FA-101 are 0 dB so you don't seem to suffer
from that problem...
cheers,
daniel