Danny Maupin wrote:
> 
> We have been working on a project involving the Assabet/Neponset
> combination.
> 
> We have also changed the display for 320x240 Active to a 640x480 passive
> display. (Display IF board and Modified sa1100fb.c) The system works fine.
> Microwindows runs on it with fine resolution, looks good.
> 
> When we installed the pcmcia support with the LP-E Compact Flash ethernet
> card the video flashes or skews when the card is connected to the network.
> If I unplug the ethernet cable everything is OK again.
> 
> The network works great but the video flashes.
> 
> Using linux-2.4.0-test11-rmk1-np3 ramdisk with pcmcia support.
> Loading with angelboot.
> 
> Any Suggestions.

BTW, you should observe the same problem when using SMC91C96 ethernet
on Neponset too.  ; )

Yes!  : )

Take a look at the Assabet and Neponset schematics. There are three different
signals that you should investigate. They are: SA_RDY, nPWAIT and nIOIS16. All
three of these signals are driven by Open-Drain outputs. Pull-up resistors are
used to "drive" these signals high when they are not be driven low by anything.

If you review the Assabet and Neponset schematics, you will find that in all
places where these signals need to be pulled up, a 100KOhm pull-up is used.

The SA_RDY signal is only PU'd at the SA-1110. While nPWAIT and nIOIS16 all require
PU's at the PCMCIA/CF sockets themselve. So there should be 6 PU's total across
the three possible PCMCIA/CF sockets on Assabet and Neponset. Of course, the ones
that matter to you depend on your hardware config: standalone Assabet or 
Assabet+Neponset.

Anyway, 100KOhm is good for long battery life. But really bad for performance
of variable latency access devices such as the LP-E. Take a look at the strobes
to the device during access. You should observe that cycles take a bout 1.5uS
to complete. EEEK!  In particular, look the the SA_RDY and nPWAIT signals during
these accesses and observe that they are "released" after about 150nS and then
__ssslllooowwwlllyyy__ get pulled high!

Try using 10KOhm. You should see a big imporvement!

  
> 
> Dan
> +++++++++++++++++++++++++++++++++
> Danny Maupin
> Senior Software Engineer - X Project
> 
> Fluke Networks Colorado
> 6805 Corporate Drive, Suite 100
> Colorado Springs, CO   80919
> 
> [EMAIL PROTECTED]
> 719.598.3842 x673
> ++++++++++++++++++++++++++++++++++
> 
> _______________________________________________
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