USB 56k modems

[Man-wai Chang ToDie (33.6k)]

Are they all hardware modems, ie controller-based?

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[Paul]

Are they all hardware modems, ie controller-based?

This one claims to be hardware based.

http://www.newegg.com/Product/Product.aspx?Item=N82E16825164005

It uses a Conexant CX93010, described here. The Conexant
chip has a built-in DSP (digital signal processor).

http://www.conexant.com/products/entry.jsp?id=539

*******
This one, on the other hand, is a "soft modem".

http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16825134003

"Device Manager identifies this modem not as "Trendnet" but
as 'Agere Systems USB 2.0 Soft Modem' "

And the Agere catalog, PDF page 5, says "soft modem stack"
for the SV92U2 chip, so the signal processing is done by the
host processor. That means the Trendnet product would behave
like a Winmodem.

http://www.agere.com/docs/PCS_Catalog_052606.pdf

*******
So there are examples of both types around. Naturally,
a chip like the SV92U2 is dirt cheap to make, due to
its simplicity. But on the other hand, you have to
install drivers ("soft modem stack") to use it. There
is an art to making good drivers of that type.

Paul

 

[Man-wai Chang ToDie (33.6k)]

This one claims to be hardware based.

http://www.newegg.com/Product/Product.aspx?Item=N82E16825164005

It uses a Conexant CX93010, described here. The Conexant
chip has a built-in DSP (digital signal processor).

I asked my cousin to order the one from US Robotics, no stock....


--
@~@ Might, Courage, Vision, SINCERITY.
/ v \ Simplicity is Beauty! May the Force and Farce be with you!
/( _ )\ (Xubuntu 8.04.1) Linux 2.6.26.5
^ ^ 22:22:01 up 7:12 1 user load average: 1.00 1.00 1.00
? ? (CSSA):
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