--- In
Homebrew_PCBs@yahoogroups.com, Stefan Trethan >
> yes.. thanks for replying.. twice ;-) ?
>
> i guess it is because yahoo is really lame with the postings..
> huge delays everywhere today...
Yep, the first reply took 4.5 hrs to post, the 2nd reply beat the
first one by a couple of hours. --Strange, must be an artifact of
the clustered databases/stored procedures.
> As said in the other post i have problems with the 300dpi of the
printer,
> uneven pad spacing. try to tweak it, or buy another printer. how
much dpi
> do you have?
Uneven spacing is the aliasing from your 300dpi printer, even at
600dpi, it's there, but much less of an issue. You can see a little
of it on the 48pin tqfp on my website photo of the raw copper with
the newly tranfered image.
My LJ 5L is a 600dpi --I'd like to get a newer 1200dpi, but this one
works good so even the $79 (after rebate) printers you see at a lot
of stores now is hard to justify. If I didn't already have one
though, it'd be a no brainer.
I have done some work with HP III, IIp with OK results --but no
tight traces --also the toner on that one was a little more brittle --
3rd party refillable. I don't think 300dpi is up to doing .5mm pitch
tqfps though.
> i bought:
> 9 xc95144-10
> 2 xc95216-15
> 2 AD9801 (25 Msamples ADC)
> 2 ADSP2181 KS-160
> 1 ADSP21061 KS-160
> payed 30eur which is what one xc95144 would cost me otherwise.
>
>
Sounds like a pretty good deal! Also, Xilinx online store has some
better prices than a few of the electronics vendors that carry thier
products. If you ship outside of the US though, shipping costs kill
the deal.
> First project with them is a freq. counter using one cpld and
having all
> leds of the 7segm. display
> connected to a individual output. i know this is simply mad without
> scanning etc. but i have
> the I/O and i am mad. I hope to programm it in a way to display
freq. or
> period duration
> because my scope has no readout and this would be nice.. i also
will try
> to allow for
> t_low and t_high measurement. (if i fund a suitable input stage).
You could hook an oscillator to the CPLD and muliplex some of the LED
drivers; although with that many pins, as you say, you might not have
to. I'd probably pulse the outputs anyway to reduce how much power
you were sinking into the CPLD's. These little devices are pretty
cool. Much more reliable than the AMD variant pal-gal 22v10's we
used in school. Although, they don't breadboard too easy. ;')
Anyway, sounds fun. :')