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Agilent Technologies HDMP-3001 User Manual

Page 91

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91

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Bit name Reserved

Reserved

Reserved

Reserved

Reserved

LO_IFG_WATER_MARK[10:8]

R/W

R/W

Value

0

0

0

0

0

0x2

after
reset

ADDR = 0x1C7: Low Inter-Frame-Gap Water Mark

Bits 7-3: Reserved

Bits 2-0: LO_IFG_WATER_MARK[10:8] are the three MSBs of the previous register.

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Bit name Reserved

Reserved

Reserved

Reserved

NORMAL_IFG[4:0]

R/W

R/W

Value

0

0

0

0

0x0C

after
reset

ADDR = 0x1C8: Normal Inter-Frame-Gap

Bits 7-5: Reserved

Bits 4-0: NORMAL_IFG[4:0] specifies the Normal Inter-Frame-Gap which is used by the MII RX interface

to insert the minimum number of idle cycles between two MAC frames sent out onto the MII RX
bus. This value is used when the INFO FIELD RX FIFO Controller sets the IFG Selection Mode
(IFG_SEL) to Normal-IFG and sends it to MII RX interface. When the number of bytes in the RX
FIFO becomes less than or equal to the Low Inter-Frame-Gap Water Mark, IFG_SEL is set to zero
for Normal-IFG. At power-up, IFG_SEL is set to zero for Normal-IFG selection. This value remains
zero until the number of bytes in the RX FIFO becomes greater than or equal to the programmable
High Inter-Frame-Gap Water Mark.