Motorola MCF5282 ユーザーズマニュアル
17-28
MCF5282 User’s Manual
MOTOROLA
Programming Model
17.5.4.5 Ethernet Control Register (ECR)
ECR is a read/write user register, though both fields in this register may be altered by
hardware as well. The ECR is used to enable/disable the FEC.
hardware as well. The ECR is used to enable/disable the FEC.
31
25
24
23
16
Field
—
X_DES_ACTIVE
—
Reset
0000_0000_0000_0000
R/W
R/W
15
0
Field
—
Reset
0000_0000_0000_0000
R/W
R/W
Address
IPSBAR + 0x1014
Figure 17-7. Transmit Descriptor Active
Register (TDAR)
Table 17-15. TDAR Field Descriptions
Bits
Name
Description
31–25
—
Reserved, should be cleared.
24
X_DES_ACTIVE Set to one when this register is written, regardless of the value written.
Cleared by the FEC device whenever no additional “ready” descriptors
remain in the transmit ring. Also cleared when ECR[ETHER_EN] is
cleared.
remain in the transmit ring. Also cleared when ECR[ETHER_EN] is
cleared.
23–0
—
Reserved, should be cleared.
31
16
Field
—
Reset
1111_0000_0000_0000
R/W
R/W
15
1
0
Field
—
ETHER_EN RESET
Reset
0000_0000_0000_0000
R/W
R/W
Address
IPSBAR + 0x1024
Figure 17-8. Ethernet Control Register (ECR)