
MSC8122 Technical Data, Rev. 13
1-6
Freescale Semiconductor
Signals/Connections
HD46
D46
ETHTXD0
Input/ Output
Input/ Output
Output
Host Data Bus 46
Bit 46 of the DSI data bus.
System Bus Data 46
For write transactions, the bus master drives valid data on this line. For read transactions, the slave drives
valid data on this bus.
Ethernet Transmit Data 0
In MII and RMII modes, bit 0 of the Ethernet transmit data.
HD47
D47
ETHTXD1
Input/ Output
Input/ Output
Output
Host Data Bus 47
Bit 47 of the DSI data bus.
System Bus Data 47
For write transactions, the bus master drives valid data on this line. For read transactions, the slave drives
valid data on this bus.
Ethernet Transmit Data 1
In MII and RMII modes, bit 1 of the Ethernet transmit data.
HD48
D48
ETHTXD2
Reserved
Input/ Output
Input/ Output
Output
Input
Host Data Bus 48
Bit 48 of the DSI data bus.
System Bus Data 48
For write transactions, the bus master drives valid data on this line. For read transactions, the slave drives
valid data on this bus.
Ethernet Transmit Data 2
In MII mode only, bit 2 of the Ethernet transmit data.
In RMII mode, this pin is reserved and can be left unconnected.
HD49
D49
ETHTXD3
Reserved
Input/ Output
Input/ Output
Output
Input
Host Data Bus 49
Bit 49 of the DSI data bus.
System Bus Data 49
For write transactions, the bus master drives valid data on this line. For read transactions, the slave drives
valid data on this bus.
Ethernet Transmit Data 3
In MII mode only, bit 3 of the Ethernet transmit data.
In RMII mode, this pin is reserved and can be left unconnected.
HD[50–53
]
D[50–53]
Reserved
Input/ Output
Input/ Output
Input
Host Data Bus 50–53
Bits 50–53 of the DSI data bus.
System Bus Data 50–53
For write transactions, the bus master drives valid data on this bus. For read transactions, the slave drives
valid data on this bus.
If the Ethernet port is enabled and multiplexed with the DSI/System bus, these pins are reserved and can
be left unconnected.
HD54
D54
ETHTX_EN
Input/ Output
Input/ Output
Output
Host Data Bus 54
Bit 54 of the DSI data bus.
System Bus Data 54
For write transactions, the bus master drives valid data on this line. For read transactions, the slave drives
valid data on this bus.
Ethernet Transmit Data Enable
In MII and RMII modes, indicates that the transmit data is valid.
Table 1-5.
DSI, System Bus, Ethernet, and Interrupt Signals (Continued)
Signal Name
Type
Description