Ethernet MAC
UG0331 User Guide Revision 15.0
405
[11:10]
Reserved
0x0
Reserved
[9:0]
COLLISION WINDOW
0x37
This programmable field represents the slot time or collision
window during which collisions might occur in a properly
configured network. Since the collision window starts at the
beginning of the transmission, the preamble and start frame
delimiter
(
SFD) are included. The default of 0x37 (55d)
corresponds to the count of the frame bytes at the end of the
window.
Table 351 •
MAX_FRAME_LENGTH
Bit Number
Name
Reset Value
Description
[31:16]
Reserved
0x0
Reserved
[15:0]
MAXIMUM FRAME
LENGTH
0x600
This programmable field sets the maximum frame size in
both the transmit and receive directions.
Table 352 •
TEST
Bit Number
Name
Reset Value
Description
[31:4]
Reserved
0x0
Reserved
3
MAXIMUM FRAME
LENGTH
0x0
Setting this bit causes the MAC to backoff for the maximum
possible length of time. This test bit is used to predict the
backoff times in Half-duplex mode.
2
REGISTERED
TRANSMIT FLOW
ENABLE
0x0
Registered transmit Half-duplex flow enable.
1
TEST PAUSE
0x0
Setting this bit allows the MAC to be paused via the host
interface for the testing purposes.
0
SHORTCUT SLOT
TIME
0x0
This bit allows the slot time counter to expire regardless of
the current count. This bit is for the testing purposes only.
Table 353 •
MII_CONFIG
Bit Number
Name
Reset Value
Description
31
RESET MII MGMT
0x0
Setting this bit resets MII Mgmt. Clearing this bit allows MII
Mgmt to perform Mgmt read/write cycles as requested via the
Host Interface.
30:6
Reserved
0x0
Reserved
Table 350 •
HALF_DUPLEX
(continued)
Bit Number Name
Reset
Value
Description