I am working with a piece of software that requires synchronous
operation of an Echo Gina 24 card. I am using the WDM driver, not the
PureWave, because I would like to be able to use this same solution
with other audio cards in the future.

The software sends a series of tones, then measures the reflections.
I have configured my software to run at 22,050 samples / second, but I
cannot detect the reflection unless I lock the sample rate at 32,000
or higher. Programmatically, I am getting all zeros, although I do
get jumps on the Gina Console VU meter.

Can anyone give me any insight as to what the Sample Rate Locking is
doing?

Tone wrote:

I am working with a piece of software that requires synchronous
operation of an Echo Gina 24 card. I am using the WDM driver, not the
PureWave, because I would like to be able to use this same solution
with other audio cards in the future.

The software sends a series of tones, then measures the reflections.
I have configured my software to run at 22,050 samples / second, but I
cannot detect the reflection unless I lock the sample rate at 32,000
or higher. Programmatically, I am getting all zeros, although I do
get jumps on the Gina Console VU meter.

Can anyone give me any insight as to what the Sample Rate Locking is
doing?
Ironically, I bet your problem lies within the WDM driver. I'm not an
expert, but the README for the Purewave drivers suggests frustration by
the echo software people in having no control over their hardware via
the WDM driver. That's the main reason they developed Purewave.

CD

Tone wrote:

I am working with a piece of software that requires synchronous
operation of an Echo Gina 24 card. I am using the WDM driver, not the
PureWave, because I would like to be able to use this same solution
with other audio cards in the future.

The software sends a series of tones, then measures the reflections.
I have configured my software to run at 22,050 samples / second, but I
cannot detect the reflection unless I lock the sample rate at 32,000
or higher. Programmatically, I am getting all zeros, although I do
get jumps on the Gina Console VU meter.

Can anyone give me any insight as to what the Sample Rate Locking is
doing?
Ironically, I bet your problem lies within the WDM driver. I'm not an
expert, but the README for the Purewave drivers suggests frustration by
the echo software people in having no control over their hardware via
the WDM driver. That's the main reason they developed Purewave.

CD

Ironically, I bet your problem lies within the WDM driver. I'm not an
expert, but the README for the Purewave drivers suggests frustration by
the echo software people in having no control over their hardware via
the WDM driver. That's the main reason they developed Purewave.

CD

This is my thought as well. Using the WDM driver bears a strong
appeal because of the flexibility of using different hardware with our
application. I need to exhaust this possibility of using WDM before
throwing in the towel.

Can anyone give me specifics of ways around WDM latency issues? One
person suggested using an external clock. Has anyone else run into
these problems?

Ironically, I bet your problem lies within the WDM driver. I'm not an
expert, but the README for the Purewave drivers suggests frustration by
the echo software people in having no control over their hardware via
the WDM driver. That's the main reason they developed Purewave.

CD

This is my thought as well. Using the WDM driver bears a strong
appeal because of the flexibility of using different hardware with our
application. I need to exhaust this possibility of using WDM before
throwing in the towel.

Can anyone give me specifics of ways around WDM latency issues? One
person suggested using an external clock. Has anyone else run into
these problems?