[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [linrad] Linrad 01.09: Soundcard Test Mode



Hi Leif!
Hi all!

Thank you Leif for the bug fix, the oscilloscope works now. 

Using this function for further investigations concerning my cpu-load
(overrun errors at high input levels) problem, I found some new details.

On my 2GHz CPU with Delta44 Card the cpu-load ("Graph:") rises up to
99.99%,
as the input signal reaches a certain level. Signals lower than this
level produces a cpu-load of approx. 3-5% ("Graph:"). 

This level is approx. +/-4100 (AD max/mix values) using linrad-01.09.

I've tried the last 00.xx version also with no difference (except the
min/max readings).
Here is also a very rapid change from 3-5% to 99.99%, as the signal
grows above this
particular level.

My Toshiba 3000 (0.9GHz) behaves in the same manner.

A short try on my pc in QRL (P2/350MHz, Soundblaster) gives other
result:
Cpu-load grows up to approx. 50% when a screen filling signal is
displayed. 

Note: in lack of an audio signal generator in my QRL, I've switched to
-54 dB to see the noise floor of the sound card (in sound card test
mode/oscilloscope). Maybe this is not equivalent to testing with real
signals -  I don't know.

Back on the 2GHz machine, I've tried different screen resolutions
(640x480 and 1014x768) 
with no better result.

The video card is configured as: "chipset VESA" in "libvga.config".

Any hints where to tweak?

73,
OE1GCA
Gerhard
--
LINRADDARNIL
/