[En-Nut-Discussion] Re: RE: Full Duplex operation

[Stephen Noftall]

> Stephen, did you have any luck simulating the 9346?
> I tried my own solution yesterday with just clk and dataout.  The rabbit
> solution requires datain as well.
> I tried looking at the clk bit in the realtek page3 9346 register so I
> wouldn't need a separate pin on the processor.  Didn't work on first
> try.

I tried that as well, hoping that the register would be able to show the
EEPROM lines while the 8019 was reading from the EEPROM, but no luck.
Although the datasheet says it is active even when in self programming mode,
it just reads back the same all the time.

I was close to getting it working today with just CLOCK and DOUT, but was
getting confused because I couldn't change any of the CONFIG registers. Then
I realized since the 8019 is set to "jumper" configuration, only config3 is
really changeable via the EEPROM. So a few more hours at it, and it will
probably start working. Then I was going to throw it into the reset code of
the driver and test it out in half duplex. I was just going to do clock
counting so only need 2 lines, but I don't know how accurate that will be.
The 8019 data sheet shows the clock not toggling while the data is being
read from the EEPROM. Well, that is incorrect ;-). So I don't know how much
I would trust the datasheet. If I don't use CS or DIN, then I want to be
very sure that the chip will allways startup the EEPROM read sycles the same
way. Hmmm, to be safe it probably would require using DIN as well, like the
Rabbit. I will keep you posted. 3 Wires onto that 8019 is tricky stuff!

For my ultimate solution though, I am redesigning the board to use the
LAN91C111. It supports auto-negotiating, so no worries.

SN