Re: 2E & USR X2

Frank Heinzius (frimp@mms.de)
Tue, 17 Dec 1996 16:36:54 +0000

Hi,

On 17 Dec 96 at 8:33, Stephen Zedalis wrote:

> On Tue, 17 Dec 1996, Christian Gatti wrote:
>
> > How about USR-Courier-I modems (external ones) on a PM2?
> > Would it not be possible that these modems can do 33.6;
> > 56 and ISDN altogether on a PM2?
> >
> > They are connected via BRI, this means a digital connection.
>
> Yes, but within the Courier-I there is a A/D conversion from the BRI to
> the old Courier chipset. So, this may not work. In fact, I thought I
> heard a USR rep say the only USR setup that will work is the all
> digital Total Control racks. That even the ones with analog cards will
> not work.

Wrong. The "old Courier chipset" is a true DSP based modem, no
Rockwell sh*t other "modem" manufacturers use. Therefore, there is no
A/D conversion to the BRI interface, just a direct DSP link.
Therefore and due to the 56k theorems (see Shannon), the I-Modem is
able to serve as an X2 host.

Frank

--
Frank M. Heinzius             MMS Communication GmbH
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