[En-Nut-Discussion] Memory error with second RTL8019

[Harald Kipp]

Stefan,

It definitely looks like an address conflict and I can't believe
(sorry) that it doesn't matter wether PD5 (Ethernet Controller
address bit 15) is high or low.

I would connect all address lines to both Ethernet boards in
parallel and use two different addresses.

There's one jumper on RTL8019AS ISA boards, which selects wether
to use the jumper or the EEPROM settings. However, some boards
offer EEPROM settings only.

There is no black magic on the Ethernut board, except may be tying
the EEEPROM input of the RTL to high level, because not all bits
could be changed through the configuration registers. But they are
perfect when set high.

Note, that the current Realtek driver will ignore the IRQ specified
in NutRegisterDevice. You need to modify the driver. This may become
worse, because using a variable base address produces slower code.
There are plans to switch from the variable "base" to a defined
constant. You may need to driver instances when using two Ethernet
interfaces.

Harald