discuss-gnuradio
[Top][All Lists]
Advanced

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

Re: [Discuss-gnuradio] FrontEnd4702 take 2


From: Matt Ettus
Subject: Re: [Discuss-gnuradio] FrontEnd4702 take 2
Date: Wed, 25 Feb 2004 10:04:28 -0800
User-agent: Internet Messaging Program (IMP) 4.0-cvs

Quoting Eric Blossom <address@hidden>:

> This still leaves a snafu regarding using the aux_DAC outputs for AGC,
> since there aren't enough of them for each card to have it's own, let
> alone two.

No it doesn't.  Each TX/RX pair gets 4 shared DAC outputs.  There are 8 total
DAC outputs on the board, 4 for each TX/RX pair.  So using 2 for an RX board is
fine.

> The Analog Devices AD8801 TrimDAC would do the job.  It's kind of
> overkill, but it would work.  It's got 8 8-bit DACs in it, and runs on
> the 3 wire SPI bus at 3.3V.  You'd still need the single-supply
> rail-to-rail op-amp at +5V to get the range right.  The daughtercards
> each support SPI with board specific enables.  There are probably
> similar parts from other vendors.

Totally unnecessary.

> I heartily agree.  We ought to be able to plug the daughterboards in
> to any slot without setting jumpers, and they ought to work.

If the 4702 followed the A2/A1/A0 convention, that would be simple.  Since it
doesn't, we have to work with what we have.

Matt




reply via email to

[Prev in Thread] Current Thread [Next in Thread]