Hello,

     I'm working on a small board with a PIC18F4525-I/P and a RTL8019AS. 
Right now I'm only trying to make the communication work. The connection 
between the RTL and the PIC is identical to another board I have that is 
working ok.

     The fact is that it doesn't work. I'm noticed a very strange 
behaviour that I would like someone to told me if this is right or 
problematic. When the PIC sends data (PORTD) to RTL (SD0 to SD7) the 
waveform is the spected "square" waves. But, when the RTL is sending 
data to the PIC (PORTD pins are changed to input) there's slow risetimes 
of 1.2us and very fast falltimes (7.0ns, measured with a digital scope).

     Is this behaviour normal? I noticed that the other board (the 
working one) shows similar behaviour regarding the risetimes and falltimes.

     If you would like to see the schematic of the communication part of 
this board please take a look at 
http://brusque.dyndns.org:8080/temp/net_board.png.

     In fact there's not much thing besides communication, only some 
74HC595 latches and connectores.

     Thank you very much,

     Brusque
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