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NXP Semiconductors
AH1721
SJA1105SMBEVM UM
AH1721
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2018. All rights reserved.
User Manual
Rev. 1.00
— 16 July 2018
8 of 35
4.4 TJA1102 PHYs for 100BASE-T1
The TJA1102 is an OPEN Alliance 100BASE-T1 compliant Dual Ethernet PHY optimized
for automotive use cases. The device provides 100Mbit/s transmit and receive capability
over a single Unshielded Twisted Pair (UTP) cable, supporting a cable length of up to at
least 15 m. Optimized for automotive use cases such as IP camera links, driver
assistance systems and back-bone networks, the TJA1102 has been designed to
minimize power consumption and system costs, while still providing the robustness
required for automotive use cases.
The default configuration of the TJA1102 PHYs on the SJA1105S Evaluation Module are
detailed in Table 2, together with the interconnection to the switch ports. The
PHYs’
default configuration can be overruled by issuing SMI commands to the PHY.
Table 2.
Ethernet port usage and default PHY configurations
MAC:
PHY/Peer
MII mode:
Connector
SMI
address:
Master / Slave:
Switch A0
Proc Port0
MII-Lite
-
-
-
Switch A1
U19, TJA1102S
RMII
J11
4
Master
Switch A2
U18, KSZ9031
RGMII
P2
2
-
Switch A3
U17, KSZ9031
RGMII
P1
3
-
Switch A4
Switch B4
SGMII
-
-
-
Switch B0
U21A, TJA1102
RMII
J14
6
Master
Switch B1
U21B, TJA1102
RMII
J15
7
Master
Switch B2
U20A, TJA1102
RMII
J12
8
Master
Switch B3
U20B, TJA1102
RMII
J13
9
Master
Switch B4
Switch A4
SGMII
-
-
-
Proc Port0
Switch A0
MII-Lite
-
-
-
Proc Port1
J4
MII-Lite
J4
1
-
4.5 PHYs for copper ethernet
For the two GBit (1000BASE-T) ports A2 and A3 the KSZ9031 PHY is used. The two
PHYs are connected to Switch-A via RGMII.
The single FE (100BASE-
TX) port, which makes the MPC5748G’s 2
nd
ethernet port
available, uses a DP83848 PHY.
The copper ethernet PHYs are configured to allow autonegotiation. This requires SW
assistance to configure the MACs in the switch or the in the µC to the interface speed.
4.6 CAN interface
The SJA1105SMBEVM features a CAN interface, which is implemented with one of the
MPC5748G’s FlexCAN-controllers and the TJA1145TK/FD CAN transceiver. In the
example project, the CAN-interface is configured with 100kbps and a payload size of
8Byte. FD extensions are not used.
The TJA1145TK/FD requires a configuration setting via SPI before it can forward data.
This is also done in the example project.