Serial
Interfaces
©
PHYTEC Messtechnik GmbH 2010 L-750e_1
49
PHY TX and RX pins accordingly. The Ethernet PHY also features
LinkMD cable diagnostics, which allows detection of common cabling
plant problems such as open and short circuits.
The physical memory area for the Fast Ethernet controller is defined
in
Table 18
.
Address
Function
0x5003 8000 – 0x5003 81FF
Control/Status Registers
0x5003 8200 – 0x5003 83FF
MIB Block Counters
Table 18:
Fast Ethernet controller memory map
In order to connect the module to an existing 10/100Base-T network
some external circuitry is required. The required 49.9 Ohm +/-1%
termination resistors on the analog signals (ETH_RX±, ETH_TX±)
are already populated on the module. Connection to an external
Ethernet magnetics should be done using very short signal traces. The
TPI+/TPI- and TPO+/TPO- signals should be routed as 100 Ohm
differential pairs. The same applies for the signal lines after the
transformer circuit. The carrier board layout should avoid any other
signal lines crossing the Ethernet signals.
An example for the external circuitry is shown in the phyCARD's
Design Guide.
If you are using the applicable Carrier Board for the phyCARD-M
(part number PBA-A-01), the external circuitry mentioned above is
already integrated on the board (refer to
section 17.3.4).
Caution!
Please see the datasheet of the Ethernet PHY as well as the
phyCARD's Design Guide when designing the Ethernet transformer
circuitry.
