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Ethernet Module
MCF5272 ColdFire
®
Integrated Microprocessor User’s Manual, Rev. 3
Freescale Semiconductor
11-23
11.5.13 Receive Control Register (RCR)
The RCR register,
, controls the operational mode of the receive block.
31
16
Field
—
Reset
0000_0000_0000_0000
R/W
Read/Write
15
4
3
2
1
0
Field
—
PROM MII_MODE DRT LOOP
Reset
0000_0000_0000_0000
R/W
Read/Write
Addr
MBAR + 0x944
Figure 11-17. Receive Control Register (RCR)
Table 11-20. RCR Field Descriptions
Bits
Name
Description
31–4
—
Reserved, should be cleared.
3
PROM
Promiscuous mode. All frames are accepted regardless of address matching.
2
MII_MODE
MII mode enable. Selects the external interface mode. Setting this bit to one selects MII
mode, setting this bit equal to zero selects seven-wire mode (used only for serial 10 Mbps).
This bit controls the interface mode for both transmit and receive blocks.
1
DRT
Disable receive on transmit
0 Receive path operates independently of transmit (use for full duplex or to monitor transmit
activity in half-duplex mode).
1 Disable reception of frames while transmitting (normally used for half-duplex mode).
0
LOOP
Internal loopback. If set, transmitted frames are looped back internal to the FEC and the
transmit output signals are not asserted. The system clock is substituted for the E_TxCLK
when LOOP is asserted. DRT must be set to zero when asserting LOOP.