Programming Model

Field

Reset

R/W

Field

Reset

R/W Address

31

25

24

23

16

 

X_DES_ACTIVE

 

 

 

 

 

 

 

0000_0000_0000_0000

 

 

 

 

 

 

 

 

 

R/W

 

 

 

 

 

 

 

15

 

 

 

0

0000_0000_0000_0000

R/W

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.

 

 

 

23–0

Reserved, should be cleared.

 

 

 

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.

Field

Reset

R/W

31

16

1111_0000_0000_0000

R/W

15

1

0

Field

Reset

R/W Address

ETHER_EN

RESET

 

 

 

0000_0000_0000_0000

R/W

IPSBAR + 0x1024

Figure 17-8. Ethernet Control Register (ECR)

17-28

MCF5282 User’s Manual

MOTOROLA

Page 384
Image 384
Motorola MCF5282, MCF5281 user manual Ethernet Control Register ECR, Xdesactive, Etheren Reset