FPGA Central

Hello,

How to set in assemblers program, that I want to perform only 1 channel. (
from C/A A/C )
Actually how to set that the 2181 should receive data just from 1 channel
and send to 1 channel.??
I taked the look to the examples in VisualDSP, but ewerywhere there is set
to left and right.

I have set the rx_buf[] and tx_[] like a 2 world length ( not a 3 ). In the
examples ther is somethink like this:


0xccc0 /* miscellaneous information reg
b7 : 1=16 slots per frame, 0=32 slots per frame
b6 : 1=2-wire system, 0=1-wire system
b5-0: res */

Its a sending to codec at initialization. I changed the 7'th and 6'th bits
to "0". And can't hear anything.

What more I should to set.





Thanks, Pool

Hi,

> Actually how to set that the 2181 should receive data just from 1 channel
> and send to 1 channel.??
> I taked the look to the examples in VisualDSP, but ewerywhere there is set
> to left and right.
>
> I have set the rx_buf[] and tx_[] like a 2 world length ( not a 3 ). In the
> examples ther is somethink like this:
>
>
> 0xccc0 /* miscellaneous information reg
> b7 : 1=16 slots per frame, 0=32 slots per frame
> b6 : 1=2-wire system, 0=1-wire system
> b5-0: res */
>
> Its a sending to codec at initialization. I changed the 7'th and 6'th bits
> to "0". And can't hear anything.

Have a look at the AD1847 Codec. It works in TDM mode. You'll need to
configure the Codec to see just the timeslots for the status data
(unavoidable) and the channel of interest for you, then you can have
the buffers configured for just 2 data, and not 3 as in stereo mode.

Another approach, much easier, would be just to read ONE sample from
the rx_buf[], the one of the channel you are interested in, and send
data just to one channel in the tx_buf[]. Additionaly, you could
configure the Codec to mute the channels you are not interested in.

Regards,

JaaC

>
> What more I should to set.
>
>
>
>
>
> Thanks, Pool

Yes, I'm using this method, which you said it's easier. It's really easy.

I just thought that if the 2181 send and receive just a two words of data
(not a three)
Hi has a little much time to perform my FFT code. So I was looking whe way
to do it.
Maybe I'm wrong and it,s doesn't matter ???

By the way that is TDM mode ??? I really don't know.